- American Physical Society Sites
- Meetings & Events
- Policy & Advocacy
- Careers In Physics
- About APS
- Become a Member
Increasingly, polymer and soft materials research is incorporating data-analytic techniques, including (but not strictly limited to) machine learning to classify materials and predict new properties or formulations, to extract data from natural language processing, and to inform the design of experimental assays. We solicit contributions from cutting edge research intertwining polymers and soft materials with machine learning and data. Of particular interest are efforts unifying data science with experimental research, work exploring vast existing datasets for the design of new materials, and techniques to mine data in different forms (e.g. simulation trajectories) and different sources (e.g. rheology or scattering) which elucidate fundamental polymer physics.
Organizers: Debra Audus (National Institute of Standards and Technology, firstname.lastname@example.org), Jonathan Whitmer (University of Notre Dame, email@example.com)
This session invites talks on the fundamental physics of polymer and small molecule semiconductors, as related to photonic and charge transport processes and their electronic, optical, and magnetic properties. Experimental and theoretical studies on processing-structure-function relationships in devices, including transistors, solar cells, sensors, and light emitting diodes and device physics are welcome. Contributions on the rheology of organic semiconductor solutions and the impact of solution structure on final film morphology, as well as the mechanical properties of organic semiconductor films, are also encouraged.
Organizers: Stephanie Lee (Stevens Institute of Technology, firstname.lastname@example.org), Youngmin Lee (New Mexico Institute of Mining and Technology, email@example.com)
Polar polymers synthesized by introducing polar groups on the monomers have been shown to be promising materials with desirable responses to various stimuli in applications such as actuators, capacitors, membranes and polymer batteries. However, the simple introduction of polar groups leads to dramatic changes in structure and dynamics of the polymers. These changes get reflected in the responses of the polymers to temperature, applied electric fields and solvents used in the processing. In this session, research related to electric polarization in polar polymers will be discussed. Local and non-local (due to gradients) effects of electric polarization, applied electric fields and ion solvation in affecting structure and dynamics of polar polymers will be discussed. Computational and experimental results obtained using scattering and reflectivity measurements, broadband dielectric spectroscopy, and atomic force microscopy-based measurements will be discussed.
Organizers: Rajeev Kumar (Oak Ridge National Laboratory, firstname.lastname@example.org), Yangyang Wang (Oak Ridge National Laboratory, email@example.com)
Polymers are ubiquitous in our everyday life finding a variety of applications ranging from physics to chemistry to materials science. A quantity of paramount importance for solid polymers and polymer nanocomposites is the thermal conductivity, which often significantly impacts materials performance. Therefore, a major scientific question is how to tune structure, mechanics and, thus, thermal transport of polymeric materials. For example, achieving either high conductivity (for electronic packaging/OLEDs etc.) or low conductivity (for good thermoelectrics) by macromolecular engineering. Currently, both experimental and computational approaches are being pursued to establish structure-property relationships in solid polymers. Therefore, the aim of this focus session is to bring together scientists from both theoretical and experimental communities with the goal to discuss the fundamentals that link the microscopic structural details with their mechanical and thermal response. Recent advances that reveal new insight into the molecular properties of solid polymers, especially developments of new advanced functional materials, are encouraged.
Organizers: Debashish Mukherji (University of British Columbia, firstname.lastname@example.org), Joerg Rottler (University of British Columbia, email@example.com)
The addition of nanoscale fillers to polymer materials with the goal of enhancing or tuning materials properties has been utilized over the past few decades. This focus session covers recent developments on the structure-property relationship of polymer nanocomposites that exhibit mechanical, optical, electronic, magnetic, dielectric, or barrier properties. Areas of interest include polymer and nanoparticle dynamics in nanocomposites, mechanical properties (glassy behavior, fracture, creep, and viscoelastic properties), fabrication and processing of polymer nanocomposites, semi-crystalline nanocomposite materials, structural characterization, and phase behavior. We welcome experimental and computational contributions. Recent developments based on big data and machine learning on understanding and predicting the structure-property relationship of polymer nanocomposites are also of the interest.
Organizers: Robert Hickey (Pennsylvania State University, firstname.lastname@example.org), Shiwang Cheng (Michigan State University, email@example.com)
Nanoparticle reinforcement has transformed friable elastomers into tear resistant, tough materials that pervade the modern world enabling automotive transport. Many materials have been explored as reinforcing filler and it is found that nanoaggregates provide the best reinforcement. The most common fillers are nano-aggregates of silica and carbon black with ~10 nm primary particles arranged in branched mass fractal aggregates of ~100 nm. Through emergent hierarchical networks these nanoparticles and their agglomerated networks impact properties centered on the micron scale such as tear resistance and large strain amplitude mechanical response, i.e. the Payne effect. This session explores the complex hierarchical structure and properties that emerge in nanocomposite elastomers through structural and dynamic analysis, simulation, and modeling.
Organizers: Greg Beaucage (University of Cincinnati, firstname.lastname@example.org), Julian Oberdisse (Montpellier University, Julian.Oberdisse@umontpellier.fr), Anne-Caroline Genix (Montpellier University, email@example.com)
The scientific discoveries that expand the frontier of research require scientific instruments and techniques to enable observation of the structure at multiple length scales. Recent advances in instrumentation, including in scattering, microscopy, and spectroscopy techniques, will transform how we characterize the polymer microstructure at the atomic, molecular and mesoscopic scale, as well as how we measure polymer dynamics across broad timescales. For example, high-flux coherent light sources enable X-ray ptychography and X-ray photon correlation spectroscopy, thereby opening up a new frontier for structure and dynamic characterization of polymeric materials. New microscopy techniques can image polymers at a sub-nanometer resolution with selective chemical contrast and controlled dosage to minimize sample damage. Contributions to this Focus Session will highlight recent advances in structural and dynamic characterization of complex multi-functional soft materials over a broad range of length and time scales. This includes work related to the use of X-ray, photon, neutron, and electron beams to explore structure-property relationships for polymers involved in energy, biological or mechanical applications, as well as advances in modeling and analyses to complement structural characterization. Works focused on the use of resonant X-ray scattering, contrast-varied neutron scattering, and analytical transmission electron microscopy to probe the structure and dynamics of the polymer are particularly encouraged, as well as in-operando and in-situ experiments or experiments focused on multimodal characterization techniques.
Organizers: Xiaodan Gu (University of Southern Mississippi, Xiaodan.Gu@usm.edu), Cheng Wang (Lawrence Berkeley National Laboratory , firstname.lastname@example.org)
The physical properties of polymers are governed by the self-assembly of elementary units into nano- to mesoscopic structures, driven by a cooperative interplay of dynamics across many degrees of freedoms. Additionally, the dynamics are significantly altered and influenced by environmental conditions, external stimuli, and processing conditions. Due to the wide ranges of relevant length- and time scales, obtaining a global understanding of polymer dynamics is a critical challenge in polymer science and engineering. This session focuses on recent experimental progress in discerning the associated multi-scale dynamics of polymers (melts, solutions, surfaces/interfaces) and composite systems using a suite of synchrotron X-ray and neutron spectroscopy techniques that cover wide spatial (nm - μm) and time (ps - min) domains. Contributions on computational and experimental approaches as complementary tools for synchrotron and neutron techniques are also welcome.
Organizers: Tad Koga (Stony Brook University, email@example.com), Laura Stingaciu (Oak Ridge National Laboratory, firstname.lastname@example.org), Antonio Faraone (National Institute of Standards and Technology, email@example.com)
Stimuli-responsive polymers and soft materials have been utilized for generating various shapes, motions, and functions by spatial and temporal changes in their physical and/or chemical properties due to external stimuli (i.e., temperature, light, pH, salt, electricity, humidity, etc). Such designable and programmable characteristics have created new opportunities in applications ranging from drug delivery, biomimetic systems, sensors, actuators, to soft robotics. This focus session covers recent advances in stimuli-responsive polymers, soft materials, and hybrids including fundamentals of materials, manufacturing techniques, characterization of the response, and their applications at various size scales. We welcome experimental and computational contributions.
Organizers: Jinhye Bae (University of California San Diego, firstname.lastname@example.org), Matthew Green (Arizona State University, email@example.com)
3D printing of polymers and soft materials relies on a variety of chemical and physical processes, such as thermal extrusion, hydrogel and bio-printing, laser sintering, monomer jetting and photopolymerization. For example, fused deposition modeling (FDM) (aka fused filament fabrication (FFF)), Polyjet, selective laser sintering (SLS), direct ink writing (DIW), stereolithography (SLA), and digital light processing (DLP) techniques have provided emerging opportunities to prepare complex-shaped parts and devices using a wide range of polymers, polymer composites and soft materials via versatile and high throughput platforms of additive manufacturing. Furthermore, 3D printing of soft matter using bio-printing has become important for tissue engineering and regenerative medicine. This focus session will provide opportunities to invite keynote speakers in 3D printing of polymers and soft materials and to have researchers discuss their recent findings of chemistry, physics, device and characterization of 3D printed objects.
Organizers: Chang Y. Ryu (Rensselaer Polytechnic Institute, firstname.lastname@example.org), Anthony Kotula (National Institute of Standards and Technology, email@example.com) and Jinhye Bae (University of California at San Diego, firstname.lastname@example.org)
This session is focused on polymers under dynamic external conditions, including ionizing radiation, extreme pressures and temperatures, solvent, and electric and magnetic fields. This will include chemically reactive scenarios as well as those for which chemical bonds are not necessarily broken. Topics will focus on chain scission and cross-linking reactions, network rearrangements, and ordering/disordering phenomena due to environmental variables. All of these scenarios can induce significant changes in the mechanical properties of any given polymer structure, which can be largely unknown for many systems and sets of conditions. This session will also explore the effects of various additional environmental factors, such as changes in relative humidity and different gaseous atmospheres on these systems. We wish for presentations to span experimental and computational approaches, including novel machine learning studies. Our goal is to engage a wide variety of research efforts in a synergistic discussion in areas of mutual interest.
Organizers: Nir Goldman (Lawrence Livermore National Laboratory, email@example.com), Christian Pester (Pennsylvania State University, firstname.lastname@example.org)
Nearly all polymeric materials employed for practical applications have non-equilibrium mesoscale structures critically influenced by processing. From melt-blown plastic bags, solution processed polymer membranes, to temperature-quenched block copolymers, non-equilibrium mesoscale structures are critical to practical applications as well as scientific understanding of process-dependent structure-property relationships of polymers. Recent investigations of non-equilibrium and transient structures of polymeric materials including flow and diffusion induced multi-scale mesoscale structures of polymer blends, reaction-induced microstructures of block copolymers, biopolymers, and self-assembled structures of micelles reveal that understanding process-dependent non-equilibrium structures requires multi-faceted considerations ranging from thermodynamic and chemical environments, dynamic and kinetic factors, and momentum and other field effects. This focus session aims to offer a venue to the community to review the recent progress of non-equilibrium mesoscale structures of polymer and related molecular systems to expand our understanding of the origin and controllability of non-equilibrium structures.
Organizers: Sangwoo Lee (Rensselaer Polytechnic Institute, email@example.com), Michael Hore (Case Western Reserve University, firstname.lastname@example.org), Douglas Tree (Brigham Young University, email@example.com)
Polymers and polyelectrolytes in concentrated solutions and melts undergo highly-correlated many-body dynamics that produce a complex hierarchy of viscoelastic relaxation modes in the flowing polymer liquid. These dynamics emerge from the complex interactions of polymer topology, chemistry, and charge that span many time, length, and energy scales. Understanding and controlling these dynamics is challenging but essential for controlling and improving polymer processing in industrial and biomedical applications. This focus session will broadly cover recent advances in understanding the microscopic dynamics and macroscopic rheology of polymers and polyelectrolytes and their applications.
Organizers: Vivek Sharma (University of Illinois at Chicago, firstname.lastname@example.org), Thomas O'Connor (Sandia National Laboratories, email@example.com)
The phenomenon of polyelectrolyte complexation can take many forms including coacervation, precipitations, and multilayer assembly, among others. Understanding the fundamental physics of these complexes, as well as how these complexes can be manipulated through a variety of stimuli including salt, pH, temperature is of utmost importance for a wide variety of applications including, but not limited to underwater adhesives, drug-delivery, and membranes. This focus session covers all aspects of polyelectrolyte complexation, including the structure, dynamics and rheology of complexes, advances in chemical synthesis techniques and all methods of study, as well as emerging application areas in these systems.
Organizers: Samanvaya Srivastava (University of California Los Angeles, firstname.lastname@example.org), Debra Audus (National Institute of Standards and Technology, email@example.com)
This session will focus on the emerging class of dynamic polymer networks held together by associative bonds known as vitrimers. In contrast to conventional dynamic or supramolecular networks, these systems exhibit conserved crosslink density. Studies investigating the novel physical properties of vitrimers including self-healing, recyclability, rheology, and various functional properties are welcome. Phase behavior and crystallization of these materials are also of interest. Experimental, theory and simulation work are also encouraged. Gels, including hydrogels, may be considered if the networks contain associative dynamic bonds.
Organizers: Chris Evans (University of Illinois at Champaign-Urbana, firstname.lastname@example.org), Julia Kalow (Northwestern University, email@example.com)
Molecular glasses are important models for understanding fundamental aspects of amorphous systems and also important materials for organic electronics and coatings. Systems of interest include vapor-deposited glasses, geologically-aged glasses, stable glasses, and organic semiconductor glasses. This session on molecular and atomic glasses includes theory, simulations, and experiment that explore structure and properties, including stability, energy, and relaxation processes.
Organizers: Mark Ediger (University of Wisconsin-Madison, firstname.lastname@example.org), Zahra Fakhraai (University of Pennsylvania, email@example.com)
The properties of polymer glasses under nanoscale confinement has remained poorly understood despite more than two decades of activity. The presence of interfaces can induce changes in polymer dynamics at the segmental and chain scale, the mechanical properties, and the effects tend to persist over surprisingly long length scales depending on the polymer chemistry, architecture, presence of additives such as nanoparticles or solvents, and the nature of the confining surfaces. In this session, we solicit theoretical, experimental, and computational studies of the effects of nanoscale confinement on glass-forming polymers and related materials.
Organizer: Robert Riggleman (University of Pennsylvania, firstname.lastname@example.org)
Tribology studies the friction, wear, and lubrication of interacting surfaces in relative motion. It is highly multidisciplinary, and includes complex physics, interfacial science and rheology, and materials science. Tribology is industrially relevant for many polymer surfaces and fluid interfaces, and macroscopic (tribometers) and microscopic (probe or AFM) techniques have been used for these studies. However many complexities, including heat generated through friction, surface wear that deposits debris in the lubricating fluid or on the surface, and low modulus of soft substrates, have been a challenge to fundamental understanding. In addition, the underlying physics and interfacial rheology of using functional surfaces such as those with porous structures, brushes or patterns remain largely unexplored. The purpose of this session is to provide a forum for recent experimental and theoretical developments, to improve the understanding of polymer tribology, wear and interfacial interactions and foster collaboration within the varied scientific communities.
Organizers: Saad Khan (North Carolina State University, email@example.com), Catheryn Jackson (Dow Chemical Company, CLJackson@dow.com)
Foams surround us in everyday life, from our food and drink (bread, beer, soda) to our furniture and construction materials (mattresses, seat cushions, building and appliance insulation). Various foams can be “liquid” and “solid”, stable for centuries or collapsing within seconds. The condensed phase of a foam can be a metal or polymer or even water (if stabilized by surfactant). This session aims to highlight fundamental and applied research related to physics of foams, including but not limited to their cell structure and morphology, mechanics and hydrodynamics, stability and collapse, and structure-property relationships. The session will include talks describing experimental, theoretical, and computational research.
Organizers: Valeriy Ginzburg (Dow Chemical Company, VVGinzburg@dow.com), Shaw-Ling Hsu (University of Massachussetts at Amherst, firstname.lastname@example.org), Kshitish Patankar (Dow Chemical Company, KPatankar@dow.com)
Ion-containing polymers are rapidly emerging options for energy storage and conversion, water treatment, sensors, and actuators. The current scientific thrust is to develop practically viable polymer electrolytes, especially in the solid state. Designing new materials requires a fundamental understanding of structures, dynamics, and ionic interactions within, giving rise to better transport processes of ionic carriers in polymer matrices. This session will focus on efforts to uncover and describe confinement-entitled features and mechanisms of ionic transport in ion-containing polymers. Topics will include progress in understanding and development of single-ion conductors and integration of experimental characterizations with theory and computation. We encourage contributions that quantitatively explore correlations among molecular-level structure and non-covalent interactions, multi-scale morphological ordering, ionic internal and rotational dynamics, and diffusive and/or driven ionic transport.
Organizer: Moon Jeong Park (Pohang University of Science and Technology, email@example.com)
Block copolymer (BCP) self-assembly composed of nanostructures has been extensively investigated in fundamental ways with various methods and a number of applications. Especially, BCP thin films have been at the center of attention because unlike in the bulk state, its morphological characteristics and the orientation of nanostructures are significantly different when the BCP is confined in a film geometry. The physical behavior of BCP thin films is worth particularly for being thoroughly understood not only in a pure scientific point of view, but also for various applied technologies: lithography, nanotemplating, surface modification, membranes, or optics. This focus session will unite the fundamental science and the state-of-the-art nanotechnology of block copolymer thin films, which leads to the convergence of knowledge and the renaissance of related themes.
Organizers: Du Yeol Ryu (Yonsei University, firstname.lastname@example.org), Sangwoo Lee (Rensselaer Polytechnic Institute, email@example.com), Teruaki Hayakawa (Tokyo Institute of Technology, firstname.lastname@example.org)
In this session, we aim to give a better understanding of universal factors that control polymer physics through synthesis, structure and physical properties of polymers with special architectures. In particular, we encourage researches using star polymers, hyperbranched polymers, polymer brushes, helical polymers, etc.
Organizers: Keiji Tanaka (Kyushu University, email@example.com), Reika Katsumata (University of Massachussetts at Amherst, firstname.lastname@example.org)
Biopolymers and bioconjugates represent an interesting class of materials that merge the specificity and functionality of biological components with the processability of synthetic polymers. While chemistry has enabled construction of such novel biomaterials, the physical properties, (thermo)dynamics, and self-assemblies for this class of materials has only recently been studied. In concert, simulation and theoretical work has made large strides in the description of biopolymers and assemblies. This focus session solicits contributions that demonstrate recent experimental and theoretical developments in biopolymers, bioconjugates, and self-assemblies thereof, in both solution and bulk phases.
Organizers: Daniel Savin (University of Florida, email@example.com), Thomas Angelini (University of Florida, firstname.lastname@example.org)
There is an ever-increasing demand for new technologies and products that improve our lives. This demand is leading to an overuse of precious natural resources and significant negative impact on the environment. There is a need for new strategies to generate novel products that are both effective, because of their enhanced performance, and sustainable, because of their use of renewable resources and lack of adverse environmental impact. By chemically modifying biopolymers and exploiting their self-assembly, enhanced functionalities can be achieved that can serve as the basis for new sustainable polymer materials. Additionally, methods for improving or controlling degradation behavior and investigating opportunities for recycling and upcycling materials will enhance sustainability of polymeric materials. These approaches require developing a conceptual understanding of their physical properties, underlying mechanisms and design principles, which is at the heart of new materials development. This focus session will describe leading edge research involving the most promising naturally occurring polymers and assemblies of biopolymers, including chemical modification for enhanced functionality and properties, as well as opportunities for reducing the environmental impact of synthetic polymers through enhanced biodegradation and recycling/reuse strategies.
Organizers: John Dutcher (University of Guelph, email@example.com), Meisha Shofner (Georgia Institute of Technology, firstname.lastname@example.org)
Polymer networks, gels, and elastomers are an extremely diverse class of materials, ranging from conventional thermosets to dynamic covalent systems, and from soft lubricants to reinforced hydrogels. Their properties can be designed to be static, or engineered for spatiotemporal control with or without a physical stimulus. Their unique properties arise from an interplay between network connectivity and morphology (or topology), chemical composition, molecular mobility and solubility, dynamics and reversibility, and degree of heterogeneity. Recent developments in controlled polymerization techniques and orthogonal cross-linking methods have especially permitted control over network topology and properties, and characterization of their structural features and properties has been enabled by advances in scattering, rheology, and imaging. This focus session covers recent advances in experiment, theory, and simulation of polymer networks, including model polymer networks, elasticity and fracture of swollen gels, healing and reversibility of polymer networks, mechanics of charged gels and double networks, non-linear deformations in swollen and dry network systems, bio-derived networks and gels, reconfigurable networks, novel synthetic approaches, and kinetics of cross-linking and curing.
Organizer: LaShanda Korley (University of Delaware, email@example.com)
The emergence of chirality of is one of the most ubiquitous themes in self-organized structures in soft materials, from biological assemblies of proteins, to chiral liquid crystalline phases to polymer morphologies. The session will bring together both experimental and theoretical researchers across the fields of polymer physics, soft matter and biophysics interested in characterizing and understanding the mechanisms and implications of the emergent chirality, at multiple scales in self-organizing soft matter systems. The workshop will highlight new advances in several key areas including, chirality in blocks copolymers and semi-crystalline polymers, chirality and defects in liquid crystals, the emergence of spontaneous chirality (twist-bend phases), frustrated chirality in self-assembled membranes and fibers, form and function of chiral superstructures in biological matter and geometry/theory of multi-scale chiral assemblies.
Organizer: Gerd Schröder-Turk (Murdoch University, firstname.lastname@example.org)
This focus session invites presentations related to polymer crystals and crystallization with the focus on molecular level understanding of polymer crystal structure, morphology, and crystallization pathway. Correlation of the crystalline structure, morphology and crystallization process with mechanical, transport (e.g. electron, ion, gas), and dielectric properties are of interest. Potential topics include, but are not limited to, the following studies: chain architecture and polymer crystallization, transport behavior in polymer crystal-containing systems, polymer crystallization in hybrid systems: epitaxy, graphoepitaxy and soft epitaxy; structural and morphological development of ordered polymer chains in hard and/or soft confined space; ultra-small polymer crystals; ultra-large polymer crystals; curved, scrolled and twisted crystals; polymer crystallization during processing. Both theoretical and experimental studies are welcome.
Organizers: Christopher Li (Drexel University, email@example.com), Toshikazu Miyoshi (University of Akron, firstname.lastname@example.org)
Photoelastic materials – whether liquid, solid, or gel – remain the most popular method to measure the internal stresses in materials. Previously used by engineers, the technique has received new attention in both physics and biology in the last two decades. The purpose of this Focus Session is to bring users of photoelastic materials together, to inspire collaboration and to share techniques. In biology, photoelastic gels have been used to visualize the ground forces applied my cockroaches, worms, and snakes. In granular physics, photoelastic disks have been used to characterize the dynamics of force chains. In the plant sciences, these can be applied to visualizing root growth. In the fracture mechanics, the photoelastic response reveals the directions of maximum stress. We welcome contributions on both exploratory and established projects, to report either on scientific findings or the implementation of new methods.
Organizers: David Hu (email@example.com), Karen Daniels (kdaniel@NCSU.edu); David Hu (firstname.lastname@example.org), Karen Daniels (email@example.com)
The wetting and adhesion properties of soft materials are relevant for a wide range of applications including antibiofouling and hydro/omniphobic coatings, medical dressings, water harvesters, microfluidic and MEMS/NEMS devices. In many situations, the macroscopic properties crucially depend on the physical processes localized near a line (contact line, fracture, triple line, etc...) where the two materials and a liquid/gas phase meet. The adhesion of linear elastic solids and the wetting of Newtonian fluids on homogeneous hard substrates are two ideal cases that have been studied intensively, yielding models bridging macroscopic linear behavior with contact line dynamics. Yet, beyond these idealized cases, many open questions arise concerning the local dissipative processes operating in the dynamical regimes. New and exciting applications in wetting and adhesion rely heavily on the complex rheological properties of fluids and soft solids, mechanical behavior at large deformations, and surface patterning. In the regimes of interest, the triple line is subjected to complex dissipation mechanism either localized near the contact line through steady stade motion or through spontaneous and noise-induced instabilities (stick-slip, avalanches, cavitation, pearling) at a mescoscale. While many efforts have been made over the last few years to capture these phenomena, our understanding is still very limited. This focus session aims at bringing together experimentalists and theoreticians.
Organizer: Julien Chopin (firstname.lastname@example.org); Julien Chopin (email@example.com)
Fascinating soft materials, often with intricate organizations and unusual properties that derive from shape and out of equilibrium mechanics, are ubiquitous in many biological and bio-inspired systems. Recent research investigates these biological soft materials at the interface of liquid crystals and active matter, uncovering new physical mechanisms in biology and soft materials. Examples include research in dense collections of biopolymers, bacterial suspensions, cellular tissues, and systems created from biological materials or cells coexisting with liquid crystals. This focus session will bring together experimentalists and theorists to share their recent progress on understanding the physics of these biological and bio-inspired systems in the perspective of active matter and liquid crystals. The session will promote further developments and invoke interdisciplinary efforts in unifying different frameworks to elucidate the intriguing physics of soft, biological materials from the semi-dilute to dense limit.
Organizers: Rui Zhang (firstname.lastname@example.org), Kimberly Weirich (email@example.com); Rui Zhang (firstname.lastname@example.org), Kimberly Weirich, email@example.com
This focus session targets the emergent interest in self-limiting assemblies. Unlike canonical assembly systems, which grow to unlimited sizes in equilibrium, self-limiting systems are those that assemble to well-defined, finite sizes. Assembly of multiple protein subunits into larger, yet finite-sized, superstructures is ubiquitous and functionally vital in biology, including capsids of viruses, extra-cellular protein fibers in plants and animals, and photonic structures in insects. Advances in the ability to resolve these assembly processes in spatially and temporally-resolved experiments raise new questions about optimal strategies for size-regulated assembly. Recent advances in DNA nanotechnology, nano-/colloidal-particle synthesis, and supramolecular chemistry make it possible to design and target synthetic analogs to protein superstructures, with finite sizes that can be regulated via the shape and interaction properties of subunits. Such programmable material systems, in concert with newly explored physical mechanisms for size-regulation (e.g. addressable or geometrically-frustrated assembly), raise basic questions about optimal design strategies that trade off increased complexity and information content at the scale of subunits for specificity, tunability and scalability in target structures. Finally, there are numerous examples of actively self-regulated assembly processes in cells, and recently developed approaches to design and fabricate active synthetic particles for assembly. These systems raise key questions about distinct nonequilibrium mechanisms of size control, and basic tradeoffs they pose between robustness of structural control and energetic costs of self-regulating feedback mechanisms.
Organizers: Greg Grason (firstname.lastname@example.org), Michael Hagan (email@example.com); Greg Grason (firstname.lastname@example.org), Michael Hagan, email@example.com
This session aims to bring together researchers from various electrostatic communities from GSOFT, DPOLY, DBIO, and DFD including, liquid crystal and block copolymer orientation, electrospinning, electrospray, ionic propulsion, electrophoresis of active matter, electroporation, electrowetting, electrohydrodynamics, and soft robotics.
Organizer: Jonathan Singer (firstname.lastname@example.org); Jonathan Singer (email@example.com)
Biology is full of examples where individual components, exhibiting simpler dynamical behavior, self-organize and generate emerging complex behavior as a group. These biological processes typically require an external supply of energy, as life is not in a thermodynamic equilibrium. Such complex dynamical behavior emerges at every level and scale, e.g. the collective motion of microtubules, self-organized dynamics of bacteria, the growth and preservation of tissue form or spontaneous adaptation of the mammalian cortical vasculature. These biological processes, disparate in time and length scales, all have in common dynamical self-organization and emerging time-dependent behaviors. This session aims to bring together experimental and theoretical work that highlights these phenomena in different biological systems.
Organizer: Miguel Ruiz García (firstname.lastname@example.org); Miguel Ruiz García (email@example.com)
Materials driven at the microscale, termed active matter, are at the forefront of soft matter research. The widespread interest in this topic is partly evidenced by the 15 focus and invited sessions on different aspects of this topic held during the 2019 March Meeting, sponsored by GSOFT, GSNP and DBio. Most progress to date has been made in the context of simplified model systems such as microtubule-kinesin active fluids and self-propelled colloids (Janus particles, quincke rollers etc). In order to build materials with the remarkable adaptive and responsive properties exhibited by biological systems such as the cell cytoskeleton, the frontier of active matter now lies in building multi-component composite materials where the interplay between the different components allows access to emergent phenomena not accessible in single component systems. There are numerous ongoing efforts both experimental and theoretical, in designing this next generation of active materials.
Organizers: Aparna Baskaran (firstname.lastname@example.org), John Berezney (email@example.com); Aparna Baskaran (firstname.lastname@example.org), John Berezney, email@example.com
From soft robotics to 4D printing: research labs abound with examples of smart morphable matter capable of interacting with their environment solely on the basis of their material properties. These responsive, malleable and programmable materials often derive their remarkable functional properties from their structure rather than their chemistry alone.This FOCUS sessions seeks contributions studying the fundamental and practical aspects of such morphing materials. Particularly, (1) the mechanisms of amplification of an input via the architecture of the materials and (2) the programmability of a complex response using a simple mode of actuation.
Organizers: PT Brun (firstname.lastname@example.org ), Andrej Kosmrlj (email@example.com). PT Brun (firstname.lastname@example.org), Andrej Kosmrlj, email@example.com
“Fluid--structure interaction” (FSI) has a number of different meanings to fluid mechanicians and soft matter physicists: from hydrodynamics of swimming, flying and flocking (in which a solid or elastic body with prescribed kinematics moves through a fluid), to small scale (viscosity-dominated) flows in deformable conduits such as blood vessels or microchannels in lab-on-a-chip (LOC) devices, to the motion of polymers in suspension, the dynamics of liquid crystals and the redistribution of fluid in porous gels. These problems have in common the slow flow of a viscous fluid interacting with a compliant object or boundary. The justification of the proposed focus session is that the variety and complexity of such problems at the interface of fluid mechanics and soft matter physics requires an interdisciplinary approach harnessing the skills of solid mechanicians, fluid mechanicians and soft matter physicists (including nonlinear and condensed matter physicists) to make progress on predictive models anchored on fundamental physics.
Organizers: Ivan C. Christov (firstname.lastname@example.org), Pejman Sanaei (email@example.com); Ivan C. Christov (firstname.lastname@example.org), Pejman Sanaei, email@example.com
Machine learning has generated much recent excitement within the physics community, and provides a powerful new tool to analyze and understand many physical systems. Usage of machine learning is still in its infancy, and many interesting challenges remain unexplored. What machine learning methods are most appropriate? How do we use these tools most effectively? Should experimental procedures be redesigned to take advantage of machine learning?
Organizers: Shmuel Rubinstein (firstname.lastname@example.org), Chris H. Rycroft (email@example.com); Shmuel Rubinstein (firstname.lastname@example.org), Chris H. Rycroft, email@example.com
Mechanical, biological and chemical systems have recently demonstrated the ability to realize, process and relay information in ways and at scales superior to that of traditional electronic computing.This focus session on programmable matter will address how logical operations, pattern recognition, optimization and other computing tasks may be realized in diverse material systems. Recent sessions on metamaterials, actuated structures, structures designed by artificial intelligence and robotic systems have dealt with programming matter. This session will address similar work from a different perspective.
Organizers: Zeb Rocklin (firstname.lastname@example.org), Christian Santangelo (email@example.com); Zeb Rocklin (firstname.lastname@example.org), Christian Santangelo, email@example.com
The physical properties of nonequilibrium matter can differ fundamentally from those of equilibrium systems, and mechanics is no exception. Recently, several groups have demonstrated that assemblies of active, dynamic, or driven elements can harbor unique large-scale mechanical and acoustic properties such as one-way transport, nonreciprocity, self-locomotion, and controlled amplification. While the specific realizations range from metamaterials to robotic assemblies to biological networks, they share the unifying theme that the novel mechanical behavior emerges from interactions among active building blocks. Progress in this area will involve both theoretical and computational advances to describe the elastic properties of dynamic assemblies, as well as experimental developments to fabricate and characterize candidate materials with nonequilibrium elements. This focus session aims to showcase new and future developments in this burgeoning field, and to bring together researchers from diverse disciplines to work towards a common physical framework and inspire new collaborations.
Organizers: Corentin Coulais (firstname.lastname@example.org), Jayson Paulose (email@example.com); Corentin Coulais (firstname.lastname@example.org), Jayson Paulose, email@example.com
Active matter is a prominent area of research in soft matter, given the opportunity to learn new physics (active materials are out of equilibrium), engineer new materials (e.g. "intelligent" responsive materials), and intersect with biology (e.g. cells, migratory animals, and even subcellular motor proteins are active materials). While a tremendous amount of work has focused on the physics of active matter in bulk/unconfined environments, recent work is starting to demonstrate the rich physics associated with active matter in complex environments characterized by tortuosity, confinement, and complex interactions. This is highlighted in a recent review article in Reviews of Modern Physics on "Active particles in complex and crowded environments" by Bechinger et al. This session will focus on this new direction in active matter research.
Organizer: Sujit Datta (firstname.lastname@example.org); Sujit Datta (email@example.com)
A broad variety of soft structures of current and perennial interest derive their mechanical response from properties that are less material than geometric. Symmetries, structural thinness, metric constraints such as curvature or twist, fractal dimension, complex patterning and structural correlations statistics are all geometrical quantities that can determine patterns of stress, strain and nonlinear deformations across a system. Such considerations are widespread in the soft, nonlinear, polymer and bio communities at APS. This session focuses on a variety of problems in soft mechanics where geometry plays a critical role, and showcase common themes in the emergent properties of these systems.
Organizer: Moumita Das (firstname.lastname@example.org)
What is the nature of the yielding transition in solids? Is this transition different in crystals and glasses? In spite of many years of work, and the obvious technological and scientific importance of this subject, there is no clear consensus. The purpose of this focus session will be to bring researchers from different groups to explore how these various threads of reasoning inter-connect, and to see whether a consensus, leading to greater understanding of this phenomena, is possible. This FOCUS session addresses fundamental theoretical questions that are at the heart of rigidity and flow in soft matter defined broadly, specifically from groups working on phenomena such as yielding and shear banding in systems ranging from crystals to gels to glasses.
Organizers: Bulbul Chakraborty (email@example.com), Sriram Ramaswamy (firstname.lastname@example.org); Bulbul Chakraborty (email@example.com), Sriram Ramaswamy, firstname.lastname@example.org
This focus session deals with the flow, deformation, and physics of liquid interfaces with adsorbed surface active species. Such complex interfaces have unique and rich interfacial physics that govern their behavior. Importantly, these interfacial properties affect the bulk behavior of soft matter. These interfaces are important for a range of materials and industrial processes including emulsions and foams, oil extraction/processing, coating technology, and more. There a wealth of interesting problems associated with such interfaces including adsorption, interfacial rheology, contact line mechanics, self assembly/organization, and impacts on bulk behavior.
Organizers: Gordon Christopher (email@example.com), Craig Snoeyink (firstname.lastname@example.org); Gordon Christopher (email@example.com), Craig Snoeyink, firstname.lastname@example.org
Kinetic theory is a powerful technique in theoretical physics that allows to derive an effective macroscopic description of a physical system by integrating out formally its underlying microscopic degrees of freedom. First formulated in the context of dilute gases, it is still widely used throughout the sciences nowadays. The aim of this Focus Session is twofold: (1) to provide a pedagogical introduction to this important technique accessible also to non-experts and (2) to present an overview of the state-of-the-art research employing this methodology not only in physics, but also in biology, finance and the social sciences.
Organizers: Andrea Cairoli (email@example.com), Kiyoshi Kanazawa (firstname.lastname@example.org), Tomohiko G. Sano (email@example.com).
As soft condensed matter physics has matured and grown, it is responsible to discuss a roadmap of the fundamental questions and challenges that will, along with new discoveries, influence the future of the field and to address the resources that will be needed. A previous NASA sponsored workshop in 2003 produced a report that laid the ground work for new instruments on the space station and for two decades of microgravity research (https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20030112858.pdf). This workshop will produce a similar roadmap, and will foster a lively exchange of new ideas as participants will want to see that the most exciting and current science is included.
Organizers: Paul Chaikin (firstname.lastname@example.org), Sidney Nagel (email@example.com); Paul Chaikin (firstname.lastname@example.org), Sidney Nagel, email@example.com
One of the main aims of soft matter physics is to find the microscopic principles that underpin the mechanical behavior of soft materials such as gels, elastomers, composites and polymeric, structured and multiphase fluids. A main challenge in these efforts is to be able to spatially resolve the response of soft materials under applied stress or flow at the relevant length and time scales. Similarly, measurement and visualization of mechanical properties of soft biological tissues has been an area of active research in medical physics, where such information is anticipated to lead to new diagnostic capabilities. Both fields have independently seen tremendous developments in the last decades. Yet despite their overlapping aims, soft matter physics and medical physics rarely benefit from each other's progress. The aim of this focus session is to bring these two communities together and exchange expertise on measurement techniques and data analysis methods in the optical imaging domain, such as OCT, Brillouin spectroscopy, the many forms of laser speckle imaging and optical tweezing.
Organizer: Joshua Dijksman (firstname.lastname@example.org); Joshua A. Dijksman (email@example.com)
Most macroscopic systems in nature evolve in time in the presence of either extrinsic or intrinsic noise. Understanding these noisy nonlinear dynamical systems has thus always been of central importance and interest in contemporary physics. Stochastic fluctuations, noise-induced correlations, spontaneous pattern formation, and even generically scale-invariant phases play an essential role in characterizing non-equilibrium systems and constitute a highly active eld of current research, both in experimental studies as well as in analytical theory and numerical investigations. Moreover, exploring potential external control of their characteristic features has become a fertile research area in recent years, addressing the design, optimization, and emergent behavior of stochastic non-linear systems.
Although granular materials have received considerable attention, we still do not have a complete description of their collective behavior under external driving. This focus session will highlight studies aimed at understanding crystallization in both wet and dry granular materials undergoing vibration, cyclic and continuous shear, or other driving mechanisms. Studies of the evolving structure and the dynamics (such as nucleation and growth) during crystallization will help establish a theoretical framework for ordering transitions in driven, dissipative systems. We seek abstracts from interdisciplinary researchers in mechanics, physics, materials science and engineering performing experimental, theoretical, and computational studies of crystallization in granular materials. This focus session will catalyze new collaborations aimed at understanding how external driving controls the collective dynamics of granular media.
Fabric, knitted and knotted structures are ubiquitous in our every-day life. Each morning, we get dressed in clothes that serve a multitude of functions, from keeping us warm and dry, to just style. Beyond weaved textiles, knitted scarfs, gloves, hats, and seaters, are part of everyone’s wardrobe. Furthermore, our shoes often contain laces, which, after decades of trying, most of us still tie in the wrong (i.e., not in the most mechanical performant) way. Knots are also instrumental to many other activities including sailing, climbing, and surgery, where their mechanical failure can lead to drastic consequences. These technologies have been an integral part of society for millennia, even if their design, manufacturing, and usage tends to rely primarily on empirical principles. Recently, at the interface of the physics and mechanics communities, there has been an upsurge in interest to develop a predictive understanding for these class of soft/flexible structures based on fundamental principles that rely on the nonlinear mechanics of slender structures and statistical mechanics. The necessary ingredients for modeling include the geometry and topology of the filaments, (self)contact and friction, and the extent of intrinsic disorder. Part of the motivation to revisit these systems is a drive to more thoroughly rationalize their mechanical performance. Perhaps an even more significant motivation for the recent developments has been the recognition that revisiting the study of fabrics, knits, and knots can lead to novel ideas for the design of metamaterials with novel features, functions, and properties. With this focus session, we seek to bring together representatives from the various groups studying fabrics, knits, and knots to cross-pollinate research methodologies, identify previously unrecognized connections in modeling strategies, and explore new research directions. The proposed venue will provide a modern unified perspective to these systems, under the umbrella of the mechanics, geometry, and topology of the underlying structures.
In recent times, there have been significant advances in developing responsive soft materials, at the interfaces of physics, chemistry, materials science and engineering. Promising materials systems that can be made to respond, on-demand, to an external stimulus include hydrogels that can swell, magneto-rheological and dielectric elastomers that can be actuated using magnetic and electric fields and pneumatic actuators. The constitutive descriptions (e.g., using continuum mechanics) of these systems often involve challenging nonlinearities and intricate multi-physics couplings that are nontrivial. The next frontier in this class of problems is to take the existing knowledge at the material level to devise active and extremely deformable structures to enable novel devices that benefit from the interplay between their shape and distributed actuation. The large deformations that are desired from such structures introduce an additional layer of complexity due to the significant geometric nonlinearities and mechanical instabilities that may arise during actuation. Therefore, the rational and predictive design of active structures made with responsive materials requires the tackling of material and geometric nonlinearities in an integrated and fully-coupled manner. The time is ripe to start tackling the forward and inverse design of these active structures using physics-based predictive models, requiring the input of complementary communities. As such, new computational, theoretical and experimental tools are essential to understand, predict and rationally design these systems. Given the diversity of fields working on this topic, the goal of this focus session is to bring the different communities together to share emerging developments, identify challenges and to generate a common language. Progress at the interface of these fields will identify new fundamental problems centered on the couplings between material and geometric nonlinearities and enable applications including (micro-)medical devices, soft robots, deployable structures for aerospace applications, and kinetic architectural/space systems.
This focus session will explore outstanding issues related to granular flow and packing beyond simple mechanical models. Though most studies of granular materials have treated the particulates as spherical, granular materials exhibit a wide-range of complex shapes and sizes with varying material compositions and structure. This focus session will address the effect of particle shape and distribution of sizes on complex, nonlinear granular flows including shear thinning, shear thickening and jamming of dense suspensions and dry granular materials.
The discovery of the Gardner transition in hard sphere glasses has led to a number of advances in our understanding amorphous solids, including providing an intuitive explanation for the soft vibrational modes of glasses, as well as predictions for the critical exponents of jammed packings. This focus session will highlight work focused on expanding our current theoretical understanding of the Gardner transition, as well as observing it in experiments and simulations. Therefore, we seek abstracts from researchers performing experimental, theoretical, and computational studies of the Gardner transition. This focus session will continue the dialogue between the jamming and glass communities, which will enable continued rapid progress in solving the glass problem.
The field of mechanical metamaterials investigates materials with properties obtained by architecture rather than composition or chemistry. The field has seen an explosion of activity in recent years largely due to the advent of advanced fabrication and computational techniques. Mechanical metamaterials have demonstrated properties that are untenable in traditional engineering materials, such as negative Poisson’s ratio, negative thermal expansion coefficient, and negative bulk modulus, and they have been shown to have novel shape changing and programmable behaviors. Many of these materials uniquely capitalize on non-linearities to achieve their properties and can be activated by external stimuli such as heat, pressure, electric fields or chemical activity. This field lies at the cusp between physics, engineering and mathematics, and this session aims to bring together researchers from diverse backgrounds to form new interdisciplinary connections. Talks will be organized around three areas of 1) design/fabrication, 2) static properties and 3) dynamic properties of mechanical metamaterials.
Recently, there has been impressive experimental and theoretical progress concerning the dynamical properties of noise-driven systems that are far-from-equilibrium. For example, researchers are now able to directly construct stationary, non-zero probability current densities in biophysical systems such as beating flagella and migrating cells. Such measurements can provide direct evidence of detailed balance violation, an essential feature in the functioning of many non-equilibrium systems. At the same time, there is substantial theoretical effort to understand fluctuation properties in such systems by proposing new quantitative approaches to characterize breaking of detailed balance. The proposed session is targeted to both experimentalists and theorists from a range of traditional fields spanning biophysics, nonlinear and statistical physics, and condensed matter physics, for whom it will be stimulating to explore common sets of new and emerging experimental techniques and analytical tools for understanding the noisy dynamics of far-from-equilibrium systems.
Power-law memory is common among various cases of systems (physical, biological, economic, social, etc.) with memory. The applications include human brain and memory, various types of biological (including human) organ tissues, viscoelastic materials, anomalous transport in Hamiltonian systems and billiards, various economic processes, and so on. Presence of memory changes the behavior of systems. In many cases the changes are quantitative, but in the case of nonlinear systems, the changes may be on the fundamental, qualitative level. A system that asymptotically has period 2^n may converge to low periodicity states (fixed point, then period two, and so on) prior to converging to the 2^n state. At the present time, this kind of behavior is not explained.
Liquids, ubiquitous on earth, are prototypical disordered condensed matter. Its very existence is remarkable, thanks to the delicate balance between interparticle potential and entropy. The phase behaviors of liquids and liquid-like matter, especially when driven out of equilibrium by extreme conditions, are exceptionally rich. Accordingly, the physics of liquids have attracted much attention in the recent decades. In addition, numerous soft and biological materials of amazing far-from-equilibrium complexity seem to share many intriguing features of liquids. Therefore, quantitative descriptions of the structure and dynamics of liquids and liquid-like matter will likely impact a wide range of disciplines in physics, chemistry, and materials science and engineering. The proposed session at APS March Meeting will focus on the forefront of the research on liquids, from fresh theoretical treatments and computations to cutting-edge experimental techniques.
Proteins underlie all biological processes; any task performed either within or by cells is coordinated through the complex interactions among proteins. Nature encodes the function of a given protein, whether it be binding, transporting or signaling, into the protein’s sequence of amino acids, which in turn defines the protein’s structure. Understanding the mapping from sequence to structure is thus vital to understanding protein interactions, and therefore the vast array of biological processes themselves. However, going from sequence to structure (i.e. protein folding) is still an unsolved problem for general sequences: the space of possible structures that a given sequence can explore is often far too vast for most molecular dynamics simulations. The inverse problem of determining what possible sequences can adopt a given three-dimensional structure is generally unsolved for similar reasons. The positions of the amino acids are highly correlated within the protein interior, and it is often unclear how changes in the sequence will affect the placement of the protein backbone. While addressing these problems has been challenging, researchers in the statistical and nonlinear physics community have made a number of recent advances. For example, studies have shown that the hydrophobic protein core is arranged nearly identically to jammed packings of non-spherical particles, which suggests a new perspective for modeling the response of proteins to thermal fluctuations, applied stress, and mutations. Protein folding and design are at the intersection of the physics of disordered systems and biological and chemical physics, and thus this session welcomes interdisciplinary researchers whose work uses experimental, theoretical, and simulation approaches to understanding protein structure and design.
“Everyone Loves a Buckling Problem” (Budiansky & Hutchinson, 1979), nevertheless, following excitement in 50s to 80s the problem of understanding when structures formed from thin elastic shells loose stability, buckle and collapse remained quite dormant for 30 years. Today, exploiting breakthroughs in computation and experiment together with the unprecedented understanding of fully nonlinear dynamical systems we are equipped better than ever to address the subtle issues surrounding the loss of stability in thin elastic systems and buckling. As a result, the problem is experiencing a renaissance where new material and methods are leverage to develop contemporary approaches to tackle the classical problem of predicting when and how thin shell structures buckle and collapse.
During the last two decades, there has been a revolution in non-equilibrium statistical physics and stochastic thermodynamics. This has allowed researchers to significantly advance and generalize Landauer's original results concerning the thermodynamics of bit-erasure into a full-fledged “thermodynamics of information processing”, analyzing computational systems ranging from information ratchets to more elaborate digital processing systems, all the way up to Turing machines. At the same time, our understanding of the information processing within biological cells has greatly expanded. This has been driving a simultaneous explosion of work on the thermodynamics of biological information processing.
Electron-phonon coupling drives conventional superconductivity. Here, phonon-mediated attraction binds electrons to form Cooper pairs. But, this effect holds at relatively weak electron-phonon coupling. Recent research has deepened our understanding of the delicate interplay between strong electron-phonon coupling and unconventional superconductivity. One approach proposes new upper bounds on Tc based on the idea that strong electron-phonon coupling promotes competing phases, and quenches coherence via enhance electron pair (bipolaron) masses [npj Quantum Materials 3.1 (2018): 59]. Other new work has found that the off-diagonal coupling, often neglected in the electron-phonon mechanism, binds pairs of small mass even at strong coupling, thus evading limitations imposed by enhanced masses, and opening a new door to phonon-driven high-Tc superconductivity [Phys. Rev. Lett. 121, 247001 (2018)]. This session will aim to synthesize developments in these opposing directions to provide a unifying front for future research.
In the past 15 years, there has been tremendous development in machine learning (ML) based on deep neural networks (DNNs), and we have seen an increasing number of talks at the APS March Meeting on applications of ML to physical and biological systems. However, despite their many successful applications, there is no theory regarding the underlying principles of DNNs, i.e., why they work and how they work. Historically, statistical physics played an important role in the initial development of artificial neural networks, such as the Hopfield model, the Boltzmann machine, and applications of spin-glass theory to neural networks. We believe time is ripe to develop a solid theoretical foundation for DNN algorithms based on concepts and methods from statistical physics. In this Symposium, we plan to bring experts from the statistical physics and machine learning community together to discuss about fundamental issues and possible directions for understanding and advancing AI research based on ideas and tools from statistical physics.
In the past 15 years, Statistical Physics has been successful as a framework for modelling complex networks. On the theoretical side, this approach has unveiled a variety of physical phenomena, such as the emergence of mixed distributions and ensemble non-equivalence, that are observed in heterogeneous networks but not in homogeneous systems. At the same time, thanks to the deep connection between the principle of maximum entropy and information theory, statistical physics has led to the definition of null models for networks that reproduce features of real-world systems but that are otherwise as random as possible. We review here the statistical physics approach and the null models for complex networks, focusing in particular on analytical frameworks that reproduce local network features. We want to give an overview on the models have been used to detect statistically significant structural patterns in real-world networks and to reconstruct the network structure in cases of incomplete information.
Active matter is a prominent area of research in soft matter and biological physics: it gives us the opportunity to learn new physics (active materials are out of equilibrium), engineer new materials (e.g. "intelligent" responsive materials), and learn more about biology (e.g. cells, migratory animals, and even subcellular motor proteins are active materials). While a tremendous amount of work has focused on the physics of active matter in bulk/unconfined environments, recent work is starting to demonstrate the rich physics associated with active matter in complex environments characterized by tortuosity, confinement, and complex interactions. In these cases, environmental interactions can strongly impact motility behaviors and collective phenomena like flocking, clustering, and phase separation. This session will focus on this new direction in active matter research.
Organizer: Sujit Datta (Princeton Univ., firstname.lastname@example.org)
First subsession: It is now indisputable that physical environment critically regulates cell and tissue function. However, it is only recently that we have begun to understand how chemical and mechanical interactions among cells shape the physiology and mechanics of tissue. This focus session will bring together a collection of experimental and theoretical work on our understanding of nuclear mechanics, single cell mechanics, and tissue mechanics, as well as how cell-cell interaction influences cell collective dynamics, tissue physiology and mechanics.
Second subsession: Living systems sense and respond to their environment via mechanisms at the molecular, cellular, and macroscopic scales. The emerging field of mechanobiophysics seeks to understand and elucidate the physical principles and mechanisms that underlie how mechanical information (such as mechanical stresses, strains, and moduli) are sensed and transmitted from molecules to cells to tissues, and how these processes impact the collective properties of cells and tissues, and their biological functions in health and disease. This Focus session presents work that explores the role of mechanics and its interplay with chemical, biological, and statistical mechanical properties in determining emergent biological properties across several spatial scales, with critical implications for development, physiology, and disease. The session will emphasize mechanobiophysics at the sub-cellular scale, the cellular scale, and the tissue scale. The invited talks will help to elucidate how mechanics impacts the structure/function properties in biology, and provide insights into how mechanical information is used and transferred across subcellular, cellular, and tissue scales. Organizers: First subsession: Mingming Wu (Cornell University, email@example.com). Second subsession: Moumita Das (Rochester, firstname.lastname@example.org)
While neurodegeneration and other brain diseases have been of great concern for decades, physics-based modeling has led to many recent results that elucidate emergence of such diseases, for example, autism. A second invited talk will outline the molecular dynamics of intrinsically disordered proteins, such as polyglutamine and alpha-synuclein pointing to the relevance of the knot formation in the folded state of proteins as a toxicity factor in Huntington disease.
Organizer: Jayanth Banavar (Univ. Oregon, email@example.com)
Social interactions shape our lives. Yet, their complexity challenges our ability to understand, model and mimic optimal social network structures. The recent advent of physics of behavior studies is providing new insights into physical principles that govern social behavior: from short range interactions, e.g. plants that utilize the infra-red visual spectrum to distinguish shade producing plants from inanimate objects, to long range interactions, e.g. insect swarms who harness air-flow fields to coordinate thermoregulation. This session will explore the boundary between such animate and related inanimate physical interactions, how social interactions are governed by physics, and vice versa, how other interactions between entities we tend to consider as inanimate could be social. We will draw from a diverse range of efforts to address it including experimental work as well as theoretical, computational, and robotic models.
Organizers: Orit Peleg (University of Colorado, firstname.lastname@example.org), Greg Stephens (Vrije Universiteit, Amsterdam, email@example.com)
The immune system is essential to our health, and yet its understanding is in its infancy. In particular, immune sensing and response, often the first steps in widely divergent systemic decisions, present key targets for manipulation and modeling. Indeed, in recent years study of these processes has yielded increasing abundance of quantitative data, along with the development of powerful theoretical and simulation methods. As a result, a community of physicists interested in immunology has been forming gradually. This Focus Session aims to bring together a broad range of experimentalists and theoreticians interested in immune sensing and response, further supporting the immuno-physics community as it gathers momentum. Keywords: Immune, immunity, cell, adaptive, innate, antibody, antigen, cytokine, ligand, receptor, signaling, feedback, sensing, thymus, spleen, lymph
Organizers: Ned Wingreen (Princeton University, wingreen@Princeton.EDU) and Amir Erez (Princeton University, firstname.lastname@example.org)
Interactions between engineered nanomaterials (such as Au, SiO2, CNT, and graphene) and biological molecules (such as proteins, DNAs, and lipid membranes) have become more and more ubiquitous in research and development. Recent advances in fabricating nanomaterials have greatly accelerated the application of synthetic sensors miniaturized down to the nanoscale for interrogating biological molecules, such as biomolecule sensors for DNA sequencing and protein analysis.
Organizers: Luan Binquan (IBM, email@example.com) and Jin He
Life is in essence a multiscale process whose elements range from single-biomolecule to network of cells. Recently, there has been a rapid growth of both interest and progress in integrating a broad range of optical microscopy and spectroscopy—the longtime workhorses of biological research—into a single instrument platform to study living matters at multiple spatial and temporal scales. This session will focus on work related to the development of multimodal hybrid optical trapping/microscopy/spectroscopy tools and their application to biological samples. The session is likely to invigorate discussion among multimodal microscopy and biophysics community, and also from other physics research groups such as condensed matter, materials, soft matter, and instrument and measurement science.
Organizer: Sang-Hyuk Lee (Rutgers Univ., firstname.lastname@example.org)
Biomaterials seen from a physics point of view, with specific attention to the structure, the function, and the relationship between structure and function, in both natural biomaterials and synthetic materials inspired by nature.
Organizer: Pupa Gilbert (Univ. Wisconsin, email@example.com)
This focus session on the influence of time-varying environments on population dynamics will assemble physicists working on a variety of biological systems from microbiology and ecology to immunology under a common physical theme. Time-varying environments have been long thought to shape evolutionary outcomes. But recent advances have provided quantitative high-throughput data sets on evolution in dynamic environments (mapping molecular fitness landscapes, tracking repertoire diversity, recording lineages). Further, we can now dynamically manipulate the environment in directed molecular evolution in the lab. Such experimental advances in multiple fields now demand that we generalize the theoretical tools of disordered systems and statistical physics to time-varying environments to confront data in this poorly understood regime of population dynamics. This session is built around an idea relevant to a broad range of biological systems, ranging from co-evolution in eco-evolution and immunology to directed molecular evolution and laboratory evolution of microbial populations.
Organizer: Arvind Murugan (Univ. Chicago, firstname.lastname@example.org)
Structure-function relationships in proteins remains an important topic attracting intense studies using increasingly sophisticated tools. Understanding the interplay of the primary structure of proteins with weak interactions during folding, dynamics, and function requires the use of quantitative approaches based on physics. Such understanding is essential not only for biological science but also for medicine and applications of proteins. This session will present both computational and experimental studies on this topic.
Organizer: Dongping Zhong (Ohio State Univ., email@example.com, and Wouter D. Hoff)
Peptides and small proteins provide powerful model systems to understand fundamental properties of proteins, allowing novel experimental and computational tools to be developed and applied. In addition, their aggregation has proven to be critical for a range of important human diseases. Recently, peptides have been shown to be capable of a surprising level of catalytic activity. Thus, peptides and small proteins provide rich and important systems at the interface of biology and physics. This session will provide an overview of current progress and novel insights in this area.
Organizer: Wei Wang and Wouter Hoff (Oklahoma State Univ., firstname.lastname@example.org)
Over the last decade there has been remarkable growth in the number of biophysicists studying the emergent phenomena present within biological populations. This increase in interest has arisen from the combination of new experimental techniques (eg sequencing) and the realization that classical theoretical ideas can now be explored quantitatively in experimentally tractable systems (e.g. clonal interference, social interactions, and multispecies community assembly). This focus session will bring together theorists and experimentalists in an attempt to advance our understanding of the evolutionary and ecological dynamics of populations and communities.
Organizer: Jeff Gore (MIT, email@example.com)
This focus session will explore the physics of cytoskeletal systems on length scales ranging from the molecular to the cellular, and across disciplines, bringing together approaches ranging from single-molecule biophysics to cell biology to theory in order to reveal the physical mechanisms underlying cellular behavior. We will focus on work that connects molecular-level features with higher-level properties of motors, cytoskeletal filaments and their assemblies. Topics in this focus session will include (1) how activities of molecular motors drive material transport along the cytoskeleton, (2) how cytoskeletal properties enable and control cellular and tissue function, (3) how stresses and other signals are transmitted and sensed in the cytoskeleton, and (4) emergent properties of cytoskeletal assemblies.
Organizers: Meredith Betterton (Univ. Colorado, firstname.lastname@example.org), Jing Xu (UC Merced, email@example.com)
Robots are moving from the factory floor and into our lives (autonomous cars, homecare assistants, search and rescue devices, etc.). However, despite the fascinating questions such future “living systems” pose for scientists, the study of such systems has been dominated by engineers and computer scientists. We propose that interaction of researchers studying dynamical systems, soft materials, and living systems can help discover principles that will allow physical robotic devices to interact with the real world in qualitatively different ways than they do now. This Focus session will bring together leaders in this emerging area, demonstrating the need for a physics of robotics and revealing interesting problems at the interface of nonlinear dynamics, soft matter, control and biology. Our goal is to establish a new field of robophysics–physics for complex “living” robotic systems (analogous to biophysics, physics for complex biological systems).
Organizers: Chen Li (Johns Hopkins University, firstname.lastname@example.org), Daniel I. Goldman (Georgia Tech, email@example.com)
The field of Morphogenesis lies at the intersection between physics, biology and engineering. Morphological shapes of biological tissues and structures have inspired scientists throughout the history, especially since the D'Arcy Wentworth Thompson's influential book titled “On Growth and Form” was published a century ago. Many recent activities have focused on understanding how biology has devised elaborated strategies for regulating pattern formation and mechanical forces in both space and time. Morphogenesis has also inspired scientists to design shape-programmable, stimulus-responsive matter. This session aims at bringing together researchers from diverse backgrounds to forge new interdisciplinary connections.
Organizers: Andrej Kosmrlij (Princeton Univ., firstname.lastname@example.org) and Zi Chen
Non-linear deformations occur in a wide range of biological processes including cell division, tissue folding and animal development. These non-linearities are often caused by the coupling of mechanical forces to biological process such as protein synthesis, chemical signaling and electrical signaling. Altering the mechanics of these deformations leads to abnormal animal behavior and developmental disorders. Understanding the causes of these deformations and how they affect biological outcomes allows us to manipulate biological systems mechanically.
Organizer: Tapan Goel (UCSD, email@example.com) and Eva-Maria S. Collins
Inference, information, and learning are subjects of emerging interest in the context of biological and physical systems. Not only do these subjects play a central role in the exploration and interpretation of experimental data, but understanding the mechanisms by which biological systems perform inference, transmit information, or learn are themselves subjects of great interest to physicists. In this session, we will explore inference, information, and learning, from a physical perspective, both as a tool for and as the subject of enquiry.
Organizer: Paul Wiggins (Univ. Washington, firstname.lastname@example.org)
Information needed by all cells to survive and proliferate is encoded in the sequence of nucleotides in genomic DNA. In eukaryotes, DNA is packaged into chromatin – a complex multi-scale structure which ensures that all chromosomes fit into the tight confines of the cell nucleus. However, DNA in this packaged state must either remain accessible to various regulatory proteins such as transcription factors, or be made accessible rapidly and robustly in response to various challenges facing the cell throughout its life cycle. This dilemma of packaging and accessibility has recently attracted a lot of attention from the biological physics community, with methods from polymer physics, statistical mechanics, and condensed matter physics being applied to understand DNA folding and dynamics, protein-DNA interactions, and chromatin structure and function. This session will focus on the latest developments in this rapidly advancing field, bringing together experimental and theoretical scientists in the fields of chromatin, DNA, and protein-DNA recognition.
Organizers: Bin Zhang (MIT, email@example.com) and Alexandre V. Morozov
This session is designed to showcase recent advances in the formulation of physical principles for understanding brain structure and dynamics. It will also highlight some of the outstanding problems whose solutions will be advanced by application of physical methods. Areas covered include: dynamics and information processing in large neural circuits, activity induced changes in circuit wiring, coordination between different types of neurons, brain-environment interaction and adaptation to natural stimulus conditions, implications for clinical applications. We expect that the opportunities explored in this session will stimulate the emergence of new physical problems as well as new application of physical methods and principles to further our understanding of the brain.
Organizer: Tatyana Sharpee (Salk Institute, firstname.lastname@example.org) and Vijay Balasubramanian (Univ. Pennsylvania, email@example.com)
Genetically identical bacterial cells are known to exhibit significant variability in their growth and division. These variations are correlated across generations due to regulatory mechanisms such as cell-size control. Thanks to recent advances in single- cell tracking technologies, the phenomenology of growth and division is being uncovered in many bacterial species. However, the molecular mechanisms behind such phenomenological models have become subjects of debate. Moreover, it has recently been shown that the details of noise and correlations in growth and division of individual cells can have significant effects on the population dynamics, which further highlights the importance of correct phenomenology consistent with molecular mechanisms. Given the recent surge of progress in different aspects of this field, this session aims to bring together theorists and experimentalist in order to provide a coherent picture of bacterial growth and reproduction that is consistent across scales.
Organizer: Farshid Jafarpour (Univ. Pennsylvania, firstname.lastname@example.org)
Macromolecular phase separation is increasingly appreciated to play a fundamental role in a wide range of cellular processes. Often these processes rely on one or more aspects of the particular material properties of the biomolecular condensates formed following phase separation of specific proteins, RNAs, or sugars. An understanding of how condensate material properties emerge from multiple weak interactions between constituent macromolecules remains elusive, as do general principles for how these properties are tuned by evolution. Progress requires quantitative measurements on diverse experimental model systems combined with new theoretical and computational frameworks to both describe sequence-dependent interactions between heteropolymers on the molecular level and to account for non-equilibrium aspects of the dynamics on the cellular scale. By bringing experimental, computational, and theoretical physicists from the polymer science, biophysics, and soft matter communities together with biologists and bioinformaticians, this focus session aims to foster interdisciplinary communication and collaboration in this exciting area.
Organizer: Patrick McCall (Max Planck Institute of Molecular Cell Biology and Genetics, email@example.com)
The session will highlight how synthetic biological engineering of cells and molecules can provide research tools for biological physics, to interrogate biological systems at all scales by delivering precise stimuli, obtaining quantitative readouts, performing parameter scans, thereby discovering quantitative principles of biological organization and function.
Organizer: Gabor Balaszi (Stony Brook Univ., firstname.lastname@example.org) and Guillaume Lambert
Energy harvesting processes in organic and hybrid perovskite photovoltaics and in natural and artificial photosynthetic systems often rely on interplay between electronic and vibrational excitations. These processes are fast, generally requiring ultrafast spectroscopic probes to disentangle. Though many applications rely essentially on the electronic energy, effects of electron-vibration coupling including polaron formation and non-adiabatic effects can be essential to the electronic properties. This Focus Symposium will highlight experimental and theoretical progress in understanding optical absorption and energy transfer processes in polymers, aggregates, single molecules, quantum dots, and hybrid perovskites, including study of singlet fission, with a focus on the electron-vibration coupling.
Probing ultrafast dynamics in molecules requires both sufficiently high temporal resolution as well as observables sensitive to the evolution of the relevant degrees of freedom; generally the nuclear and electronic character in photochemical processes. To capture the vibrational and electronic motions on their inherent timescales will require femto- and attosecond time resolution. As for the choice of observable, recent advances in both the experimental generation of tunable ultrashort X-ray pulses, as well as the computational/theoretical simulation of spectroscopic X-ray properties, has resulted in a surge of interest in the utilization time-resolved X-ray spectroscopies to both prepare and probe molecular wave packets. Of particular interest is the ability of core-spectroscopies to interrogate the time-evolving vibronic character and electronic coherences in complex molecules, be it in the form of nonadiabatic dynamics between electronic states driven by nuclear motion, or the attosecond evolution of electronic wave packets generated by broadband excitation. This symposium will bring together experimental and theoretical researchers to present recent results and evaluate the future potential of X-ray spectroscopies to image the coherent evolution of wave packet dynamics, using linear and non-linear spectroscopies in both the femto- and attosecond time regimes.
Coherent nonlinear optical microscopies provide spatially-resolved access to chemical and dynamic information, typically with minimal or no labeling, so are well-suited to address increasingly demanding characterization needs in areas ranging from materials science to biophysics. Accordingly, these techniques continue to enjoy active development and deployment. This symposium will bring together experts in the field to discuss how new techniques, theoretical models, and application areas are advancing the field and opening up new opportunities.
The importance of water across many disciplines of science and engineering cannot be overstated. Water shapes our blue planet, is a unique solvent in chemistry, the ‘elixir of life’ in biology, a key corrosion agent in engineering, and a complex fluid with a multitude of anomalies in its phase behavior in physics. Despite its importance, a full understanding of water dynamics across its phase diagram, its interaction with interfaces, and changes under confinement has remained challenging. In this symposium, we will discuss advanced experimental and theoretical aimed at unraveling the dynamical signatures of this fascinating liquid in different phases and environments.
Organizers: Mischa Bonn (MPI Mainz, Germany), Teresa Head-Gordon (UC Berkeley, USA)
Density Functional Theory (DFT), in both its ground-state and time-dependent (TD) flavors, is an exact reformulation of the quantum mechanics of many-body systems. Used in more than 40,000 papers annually, DFT provides a useful balance of accuracy and efficiency for electronic structure and response calculations in molecules, clusters, and solids. DFT is the only computationally feasible quantum mechanical approach to some of the most interesting and topical problems in chemical physics today, including catalysis, new Li battery materials, stacking interactions in DNA, phase transitions, the design of solar cells, electronic transport, laser-control of molecules and solids, ultrafast laser-induced demagnetization, time-resolved spectroscopies, and photodynamics generally. There are however many problems for which the currently used functional approximations and formulations of DFT need improvement; these applications include strongly correlated and multireference systems, transition metal chemistry, dynamics far from equilibrium, and globally accurate potential energy surfaces, and there is significant on-going progress to address these challenges. The effort to find universal methods that work well in all the areas of interest, as required for the most complex applications, also continues. At the same time, there have been significant developments in alternative methods, based on for example, many-body perturbation theory and non-equilibrium Green’s functions. This symposium highlights some of the recent advances in both theory development and applications. Note that there will also be a Pre-Meeting tutorial on DFT and TDDFT for those interested in learning about the fundamental elements in these theories. The symposium welcomes contributed talks to complement the invited talks and to broaden the scope.
Organizers: Kieron Burke (U.C. Irvine), Neepa Maitra (Rutgers University at Newark)
Molecular ensembles embedded in confined electromagnetic environments can undergo strong coupling between their collective molecular excitations and photonic modes, giving rise to hybrid light-matter states known as polaritons. Molecular polaritons have been shown to be ideal playgrounds to control thermally-activated and photoinduced processes, modify optoelectronic properties, design new spectroscopies, or even recreate exotic states of matter at room-temperature. This symposium gathers experts in theory and experiment to provide an outlook of recent chemical physics developments in the fastly growing field of molecular polaritonics.
Organizers: Joel Yuen-Zhou and Wei Xiong (UCSD)
The intersection of long-range magnetic order with topological electronic states is developing into an exciting area in condensed matter physics. A variety of exotic quantum states have been predicted to emerge, such as the quantum anomalous Hall effect, Weyl semimetals, and axion insulators. There are many open questions that in these materials that have inspired rapid theoretical and experimental developments. For example, although the exciting phenomena listed above have been predicted, only a few experimental realizations have been found to date. However, there are several candidate materials that have been proposed or synthesized very recently, some in just the last year. Thus, a focus session on theoretical predictions, experimental methods that are sensitive to the topological nature of magnetic materials, and the discovery of magnetic topological materials in both single-crystal, thin film, and heterostructure morphologies would be timely and well-attended.
Defects profoundly affect the electronic and optical properties of semiconductors. They control charge carrier concentration, transport, and recombination rates. They also regulate mass- transport processes involved in migration, diffusion, and precipitation. The success of microelectronic and optoelectronic semiconductor devices has relied on the engineering of defects in the form of dopants and interfaces, all while mitigating unwanted defects. Likewise, understanding, characterizing, and controlling dopants and defects is essential for technologies such as wide-band gap lighting and power electronics, materials for quantum information sciences, memory, and thin film solar cells. This focus topic is the physics of dopants and defects in existing and emerging semiconductors, from the bulk to the atomic-scale, encompassing point, line, and planar defects, and including surfaces and interfaces. We solicit abstracts on experimental, computational, and theoretical investigations of the electronic, structural, optical, and magnetic properties of dopants and defects in elemental and compound semiconductors, nanostructured materials such as nanowires and quantum dots, photodetectors, and light emitters. We especially encourage submissions in the areas of: (1) wide band-gap electronic materials such as diamond, aluminum nitride, gallium nitride, and gallium oxide, (2) Inorganic semiconductors for photovoltaics, and (3) semiconductor devices that are enabled by structural and deep electronic defects, e.g. materials for phase-change, phosphorescence, radiation detection, and quantum information applications. In addition, we welcome abstracts on specific, relevant techniques such as materials processing, property determination, and advanced characterization such as defect imaging and spectroscopy.
Complex oxides exhibit a rich variety of interactions between their strongly correlated spin, charge, lattice, and orbital degrees of freedom. These interactions lead to competing ground states and intricate phase diagrams that host a vast range of functional properties including: ferroelectricity, pyroelectricity, electrocaloricity, magnetoelectricity, multiferroicity, metal-insulator transitions and defect- related properties. It is these functional properties and their application to up-and-coming technologies that are the principal topics of interest for this symposium. In particular, this focus topic welcomes contributions on fundamental aspects of structure, ordering, and functionality in complex oxides as well as emerging avenues to controlling polarization, magnetism, and electronic properties via strain, composition, defects, and broken symmetry. Breakthroughs and progress in the theory, synthesis, characterization, and device implementations in these and other related topics are highly encouraged.
Fe-based superconductors (FeSCs) continue to fascinate the materials and condensed matter physics communities as we move into a new decade of their study. While the field started from the iron pnictides, new efforts have increasingly been directed towards the iron chalcogenides. Recent advances in the synthesis and control of the FeSCs are giving us renewed hope for even higher superconducting transition temperatures. Considerable progress is being made in the understanding of these materials, including the bad-metal normal state and the degree of electron-electron correlations, the order and excitations of the various electronic degrees of freedom (spin, orbital, charge and nematic), the role of quantum criticality in the phase diagram, and the amplitude and structure of the multi-orbital superconducting pairing. At the same time, there is progress in understanding the unifying principles that may optimize superconductivity of the FeSCs and connect them with other unconventional superconductors such as the cuprates, heavy fermions and organic charge-transfer salts. Finally, the FeSCs may connect to broader issues on superconductivity, such as BCS-BEC crossover and topological superconductivity. In addition to advancing our fundamental understanding of superconductivity, the unique materials parameters of FeSCs (relatively high Tc, low anisotropy, high critical fields) offer new approaches to the design of superconducting wires, magnets and thin-film devices. This focus topic will cover the pertinent recent developments in the materials growth, experimental measurements and theoretical understandings and survey the potential for discovering new superconducting systems with still higher transition temperatures, and new applications.
Transition metal materials have provided a playground to test exotic phenomena originated from strong electron-electron interactions and topology. Examples include high temperatures superconductors, metal-insulator transitions, spin-charge separations, and frustrated magnetic systems, which have been mainly based on materials with 3d orbitals. Recently, heavy transition metal materials with 4d and 5d orbitals have attracted great attention, due to their unique competition of relevant energy scales – spin-orbit coupling, exchange interactions, and crystal-field energy. As a consequence of the intricate interplay between these interactions, 5d and 4d materials exhibit intriguing properties that have been observed by various experimental techniques and theoretical methods. Few examples include unexpected insulating behavior, possible topological spin liquids with anyons, and unconventional superconductivity. This focus topic covers experimental and theoretical work on compounds containing 5d and 4d elements, e.g. iridium, osmium, rhodium, ruthenium (including, but not limited to, oxides, halides, sulfides, etc). These materials can be found for a variety of two- and three-dimensional lattices with varying degree of frustration, electronic correlations, and effective spin-orbit coupling. Emergent phases include magnetism, topological behavior, spin liquids, superconductivity and metal-to-insulator transitions.
The interest in two dimensional (2D) materials is rapidly spreading across all scientific and engineering disciplines due to their exceptional chemical, mechanical, magnetic, optical and electrical properties, which not only provide a platform to investigate fundamental physical phenomena but also promise solutions to the most relevant technological challenges. 2D materials find their immediate application in field effect transistors, gas sensors, bio-detectors, mechanical resonators, optical modulators and energy harvesting devices with superior performances that have already been demonstrated in prototype devices. Furthermore, recent progress has also shown that heterostructuring, doping, intercalation and phase engineering in these 2D materials will enable unprecedented structures and functionalities with new opportunities and great potentials. However, the true impact will only be made if the initial breakthroughs are transformed into commercial technologies. A major challenge towards the commercialization of 2D materials is the scalable and controllable production of high quality layers in a cost-effective way. So far, the best quality samples of 2D materials have been obtained through micromechanical exfoliation of naturally occurring single crystals. Chemical vapor deposition (CVD) is the most widely used bottom-up technique to grow large area 2D-materials. Several top-down approaches have also been adopted based on bulk liquid phase chemical and electrochemical exfoliation. Each type of method possesses its unique strength to enable material for specific research or application needs, whereas on the other hand has its own challenge to be addressed.
This focus topic will cover:
Research exploring 2D semiconductors is rapidly expanding to include a wide variety of layered materials and their heterostructures with diverse properties such as strong many-body interactions, strong spin-orbit coupling effects, spin- and valley-dependent physics, and topological physics. This Focus Topic will cover experimental and theoretical/computational work related to 2D semiconductors and their heterostructures, including large bandgap materials such as the chalcogenides (e.g. MoS2, WSe2, GaSe and ReSe), phosphorene and h-BN, small bandgap materials with possible topological properties (such as silicene, germanene, stanine, Bi2Se3 and WTe2), magnetic semiconductors (e.g. CrGeTe3, CrI3, Mn:MoS2), and emerging new semiconductors. We encourage abstracts discussing results on monolayers, few-layers, heterostructures including twisted bilayers and their nanostructures. Topics of interest include quantum transport, mobility engineering, the understanding and engineering of the dielectric environment and defects on optical, electronic and many-body phenomena, piezoelectric and ferroelectric effects, spin- and valley-dependent phenomena, exciton physics including Moire excitons, properties of domain walls, as well as magnetic, multiferroic, thermal and mechanical properties of 2D semiconductors. Processing and measurement techniques developed to probe van der Waals semiconductors are also welcome.
Recent experimental, theoretical and computational advances have enabled the design and realization of micro-/nano-structured materials with novel, complex and often unusual electromagnetic properties unattainable from natural materials. Such nanostructures and metamaterials provide unique opportunities to manipulate electromagnetic radiation over a broad range of frequencies, from ultraviolet and visible to terahertz and microwave. These concepts have also been extended to enable acoustic/mechanical metamaterials and metasurfaces. The transition from three-dimensioanl nanostructures and metamaterials to planar two-dimensional metasurfaces further facilitates structure fabrication, material integration, novel functionality, and system miniaturization, thereby finding a wide range of potential applications. This focus topic will highlight recent progress in the physical understanding, design, fabrication, and applications of these artificial materials. Topics of interest include, but are not limited to: nanophotonics, plasmonics, near-field and quantum optics, optofluidics, energy harvesting, and the emerging interface of condensed matter and materials physics with biological, chemical and neural sciences.
Understanding and controlling how heat, charge, and energy flow at the nanoscale is critical for realizing the potential of nanomaterials in next generation device technologies. Of particular challenge, and opportunity, is understanding how elementary excitations such as phonons, electrons, holes, excitons, and plasmons interact with each other and are influenced by interfaces, confinement, and quantum effects in nanostructures. This is particularly true for heterogeneous nanoscale materials and interfaces with varying degrees of electronic and phononic couplings, and distinct thermal and electrical impedances. Structural components used in hybrid nanostructures can be made of semiconductors, metals, molecules, liquids, etc.
Contributions are solicited in areas that reflect recent advances in experimental measurement, theory, and modeling of transport mechanisms in nanoscale materials and interfaces. Specific topics of interest include, but are not limited to:
When complex oxides are prepared as thin films and heterostructures, they exhibit additional properties that cannot be realized in the constituent materials alone. These novel properties arise as a result of interfacial charge transfer, exchange coupling, orbital reconstructions, proximity effects, dimensionality as well as the mechanical and electric boundary conditions. Emergent electronic and magnetic states at oxide interfaces raise exciting prospects for new fundamental physics and technological applications. This Focus Topic is dedicated to progress in the fabrication, methodologies, and knowledge in the field of complex oxide thin films, heterostructures, superlattices, and nanostructures. Synthesis, characterization, theory, and novel device physics are emphasized. Specific areas of interest include, but are not limited to, growth of oxide thin films and heterostructures (with special emphasis on new materials/interfaces), control of properties (magnetic, electronic, ordering, interfacial superconductivity, multiferroicity, magnetotransport, spin-orbit coupling), and developments in theoretical prediction and materials-by-design approaches. Advances in techniques to probe and image electronic, structural and magnetic states at heterostructure interfaces are also emphasized. Note that overlap exists with other DMP and GMAG focus sessions. As a rule of thumb, if complex oxides and their heterostructures are at the core of the investigation, then the talk is appropriate for this focus topic.
Technologies for processing of information are at a cross-road. Until now, advances in information processing have been mainly achieved by miniaturization and integration, such as scaling down transistor-based semiconductor technologies and heterogeneous integration in an architecture, the traditional methodology is rapidly approaching its physical limits. A new class of information processing that explores possibilities beyond classical computing architectures is now underway with particular emphasis on quantum phenomena that complement existing computing architectures. Quantum information processing, revolutionizing ways of generation, transmission, and computation of information, must be physically implemented by appropriate materials. To that end, new materials and physical properties are needed along with close collaborations among physicists, materials scientists, and electrical engineers. This Focus Topic intersects the materials discovery, devices physics, and nanoscale structure communities for quantum information processing (QIP) within the common theme of understanding the underlying physical interactions in materials for quantum information processing. Given the exploratory nature of this field, contributions are solicited broadly among the following topics:
Organic molecular solids are a challenging materials class since numerous “weak” interactions, all of comparable strength, control structures and functional properties. The promise of high performance optoelectronics, designer sensors, electrode work function control, and bioelectronic devices make the payoff for addressing this challenge high. In these applications surfaces and interface are decisive in their impact on carrier injection and transport, and on structure and morphology control. This Focus Topic will convene to discuss new experimental and theoretical/computational results aimed at the both basic and applied physics underpinning surfaces, interfaces, and thin films of organic solids. Research of interest includes the structure, properties, charge dynamics, and applications of organic adsorbates, monolayer assemblies, thin films, crystals, and nanostructures.
This session will focus on the behavior of matter under extreme conditions of pressure, strain, compression and impacts, often in combination with extreme electromagnetic fields and particle irradiation. Such research is not only of fundamental scientific importance, but it also has numerous applications, e.g. for the synthesis of materials exhibiting novel electronic and magnetic states of matter as well as unique stoichiometries and crystal structures, which require the development of new chemical bonding rules and understanding of extreme quantum coherent behavior. Such research is relevant for the design of revolutionary materials for use on Earth (explosives, tooling and armor), understanding Earth’s deep interior, as well as the evolution and qualities of planets and stars throughout the universe.
Theoretical method developments coupled with the spectacular increases in computer power have made it possible to more accurately probe the electronic structure and properties of matter, as well as push the boundaries of the time and length scales that can be probed in simulations. At the same time, new experimental techniques are being developed to accurately characterize matter at extreme conditions with state-of-the-art facilities worldwide. The proposed sessions will harness synergies between experiment and theory, which has seen a renewed resonance leading to many new discoveries.
This focus session will bring together theoreticians and experimentalists from a broad range of fields including physics, chemistry, materials science, as well as earth and planetary science and astrophysics for discussions in areas that include, but are not limited to, the following:
Organizers: Eva Zurek (University at Buffalo, email@example.com), Koichiro Umemoto (Tokyo Institute of Technology, Japan, firstname.lastname@example.org), Andreas Hermann (University of Edinburgh, UK, email@example.com), Gilbert (Rip) Collins (University of Rochester, firstname.lastname@example.org), Shanti Deemyad (University of Utah, email@example.com) Antonio M. dos Santos (Oak Ridge National Laboratory, firstname.lastname@example.org)
16.01.02 Building the Bridge to Exascale: Applications and Opportunities for Materials, Chemistry, and Biology (DCOMP, DBIO, DCP, DPOLY, DMP, DAMOP, DCMP [same as 04.01.33, 05.01.14, 01.01.48, 06.01.08]
High Performance Computing (HPC) plays a critical role in modern scientific discovery through a merging of simulation, modeling and experimental data analysis. HPC facilities around the world, are preparing to field exascale HPC systems, capable of performing more than 1018 floating-point operations per second, in the next several years. For example, the U.S. National Strategic Computing Initiative (NSCI) is currently underway with the goal of fielding exascale computers in 2021. The advent of exascale computing brings with it both tremendous opportunity for scientific discovery as well as challenges for harnessing this technology in scientific applications. This focus session will bring together researchers with experience in using high-performance cyberinfrastructure, including supercomputers, communication networks, and data resources, to achieve breakthrough scientific results in materials, biological, and chemical physics. This includes researchers at experimental facilities such as light and neutron sources with extreme data-science requirements, including machine-learning approaches, and researchers in computational materials, computational chemistry and computational biophysics with experience in large-scale simulations. Software-development projects preparing a variety of physics applications for exascale-class machines will also be presented. This session will highlight forefront examples of the state-of-the-art in computational physics today leveraging large, national-scale infrastructure.
Organizers: Jack C. Wells (Oak Ridge National Laboratory, email@example.com), Jack R. Deslippe (Lawrence Berkeley National Laboratory, firstname.lastname@example.org), Anouar Benali (Argonne National Laboratory, email@example.com)
Electron-phonon interactions play a central role in many phenomena, most classically the resistivity of metals at ordinary temperatures, and are important for electrical and thermal conductivity of thermoelectrics, the temperature dependence of the optical band gaps of semiconductors, and other phenomena such as phonon drag. This focus topic covers electron-phonon interactions emphasizing fundamental physics, direct computation, first principles and phenomenological theory, optical and phonon spectroscopy and novel effects in nanostructures, nanodevices, 2D materials, and bulk materials. This focus topic also includes the emerging area of phononics, in particular manipulating phonon eigenstates, coherent superpositions and non-linearities, for example for logical operations or to manipulate sound or heat in unconventional ways or topological acoustic materials, including active materials.
Organizers: David J. Singh (University of Missouri, firstname.lastname@example.org), Ivana Savic (Tyndall Institute, email@example.com), Matthieu Verstraete (Universite de Liege, firstname.lastname@example.org), Xiulin Ruan (Purdue University, email@example.com)
Many properties of functional materials, interfaces, and nano-structures derive from electronic excitations. These processes determine properties such as ionization potential and electron affinity, optical spectra and exciton binding energies, electron-phonon coupling, charge transition levels, and energy level alignment at interfaces. In addition, hot carriers in semiconductors and nanostructures are generated, transition between excited states, transfer energy to the lattice, and recombine with each other. It is necessary to understand these properties from a fundamental point of view and to achieve design of materials with optimal performance for applications e.g., in transistors, light emitting diodes, solar cells, and photo-electrochemical cells.
A proper description of electronic excitations requires theoretical approaches that go beyond ground state density functional theory (DFT). In recent years, Green’s function based many-body perturbation theory methods like RPA, GW, and BSE have been adopted by a rapidly growing community of researchers in the field of computational materials physics. These have now become the de facto standard for the description of excited electronic states in solids and their surfaces. Ehrenfest dynamics and surface-hopping schemes, e.g. based on time-dependent DFT, are used to describe coupled electron-ion dynamics as the origin of interesting physics in photo-catalysis, surface chemical reactions, scintillators, or radiation shielding.
Advances in high performance computing and scalable implementations in several popular electronic structure packages enable further progress. Sophisticated calculations are accessible for many users and feasible for large, complex systems with up to few hundred atoms. These methods are increasingly applied to interpret experiments, such as spectroscopies and femto- second pump-probe measurements, and to computationally design functional materials, interfaces, and nano-structures.
This focus topic is dedicated to recent advances in many-body perturbation theory and electron- ion dynamics methods for electronic excitations: challenges, scalable implementations in electronic structure codes, and applications to functional materials, interfaces, molecules, and nano-structures. It aims to attract researchers working on the nexus of electronic and optical properties of materials, hot electron dynamics, and device physics.
Organizers: André Schleife (University of Illinois at Urbana Champaign, firstname.lastname@example.org), Serdar Ogut (University of Illinois at Chicago, email@example.com), Yuan Ping (University of California, Santa Cruz, firstname.lastname@example.org), Sahar Sharifzadeh (Boston University, email@example.com)
Quantum matter, the research field studying states of matter whose properties are intrinsically quantum mechanical, draws from areas as diverse as hard condensed matter physics, quantum information, quantum gravity, and large-scale numerical simulations. Recently, the condensed matter, quantum information, and atomic, molecular, and optical physics communities have turned their attention to the algorithms underlying modern machine learning, with an eye on making progress in quantum matter research. This has led to several breakthroughs where machine learning algorithms recognize conventional and topological states of matter, including the revelation of phases of matter previously unidentified by conventional techniques in disordered spin chains, as well as the application of machine learning algorithms to spot hidden order in images of a bizarre state in high-temperature superconductors. As evidenced by the community embracing a wide array of activities related to research at the intersection of machine learning and quantum mechanics, as well as the continuous appearance of increasingly creative research activity in this area, it is clear that over the next few years, machine learning will become very important for the computational study of condensed matter, quantum information, and other areas of quantum physics. This focus topic includes, but is not limited to, topics such as machine learning many-body systems, machine learning for materials and experimental data, machine learning quantum states, and materials design and discovery.
Organizers: Juan Felipe Carrasquilla Alvarez (Vector Institute, firstname.lastname@example.org), Giacomo Torlai (Flatiron Institute, email@example.com), William Ratcliff (National Institute of Standards and Technology, firstname.lastname@example.org), Ehsan Khatami (San Jose State University, email@example.com)
Precise understanding of strongly correlated materials and models is a major goal of modern physics. Achieving this understanding normally requires four complementary ingredients and thus four distinct directions of research: (i) conducting experiments that aim at producing highly accurate data, (ii) developing effective theories addressing the relevant degrees of freedom and/or emergent phenomena characteristic of a given phase of matter; (iii) solving simplified strongly correlated microscopic models either numerically or analytically, and (iv) cross-validating theoretical predictions against empirical data qualitatively and, ultimately, quantitatively. The last decade has seen breakthroughs made in all the four directions. An impressive progress has been achieved, and more is anticipated, where models and methods from many-body physics can be tested with precision, and where entirely new systems are realized that still await their accurate description. For example, in the field of ultra-cold atoms it is now feasible to perform analog quantum simulations aiming at experimental realization of key many-body quantum models and engineer novel Hamiltonians. Controllable experimental platforms also started to address fundamental questions about non-equilibrium quantum dynamics, discovering new dynamical phases of matter with no equilibrium counterpart. The focus sessions that will bring together researchers who share the goal of achieving controllable theoretical and experimental understanding of phenomena taking place in correlated many-body systems. The key topics of the sessions may include exactly solvable models, dualities and correspondences between seemingly unrelated theories (enabling the transfer of results and ideas), first-principles numeric approaches (such as tensor network and density-matrix renormalization group methods; path-integral, stochastic-series, and diagrammatic Monte Carlo techniques, dynamic cluster approximations, linked-cluster expansions, etc.); effective coarse-grained description of quantum phases and phase transitions; analytical and numerical methods for topological phases (including quantum spin-liquids, topological insulators, fractional quantum Hall states, and Chern insulators, etc.), and precise experimental studies of strongly correlated bosonic, fermionic, and spin systems (both at and out of equilibrium).
Organizers: Nikolay Prokofiev (University of Massachusetts, Amherst, firstname.lastname@example.org),Tigran Sedrakyan (University of Massachusetts, Amherst, email@example.com), Ian Spielman (University of Maryland, firstname.lastname@example.org), Kristjan Haule (Rutgers University, email@example.com)
Our ever expanding ability to computationally interrogate idealized yet complex mathematical descriptions of disordered matter such as glasses, poly-disperse colloidal aggregates, amorphous polymers, and granular packings has provided novel means to understand their underlying physics. Oftentimes surprisingly robust structural features can be discerned to arise in systems that otherwise seem to be entirely random by nature. Concepts related to energy landscapes, polymer entanglement and non-equilibrium thermodynamics are some of the areas that have been elucidated by carefully constructed computational investigations. New algorithms for optimizing and exploring disordered systems also continue to emerge, providing tools for addressing these largely under-studied yet ubiquitous materials systems. This session will discuss applications of established computational methods toward the study of these systems as well as development of novel algorithms for their further elucidation.
Organizers: Michael Falk (Johns Hopkins University, firstname.lastname@example.org), Pengfei Guan (Beijing Computational Science Research Center, email@example.com), M. Lisa Manning (Syracuse University, firstname.lastname@example.org), Joerg Rottler (University of British Columbia, email@example.com)
Systems with a large number of degrees of freedom are fundamental for describing macroscopic behavior in a wide area of physical sciences and beyond. Consequently, statistical mechanics is one of the foundational theories for describing systems with disorder, limited microscopic knowledge and at finite temperature. Computer simulations are indispensable to advance understanding in these areas. In conjunction with modern computer architectures, new and improved algorithms and methodologies enable increased computational performance and accuracy and the study of more complex physical problems. The main focus of this session will be on new methods and capabilities of Monte-Carlo, Molecular-Dynamics and Spin-Dynamics methods and their combinations. This Focus Session aims to provide a platform to bring together researchers from different disciplines to discuss and showcase recent advancements in computational statistical physics, as well as their applications to research problems at the frontier of computational physics.
Topics include (but are not limited to): simulation algorithms or techniques in computational statistical mechanics and their related studies; implementation techniques for modern computer architectures (e.g. GPUs or many-core processors); theoretical studies and discoveries aided or enhanced by computer simulations; applications of computational statistical mechanics to the study of thermodynamics, phase stability and transitions, critical phenomena at equilibrium, disorder driven phenomena, non-equilibrium, or irreversible processes for physical systems such as spin models, solid state systems, polymers and biological systems.
Organizers: Markus Eisenbach (Oak Ridge National Laboratory, firstname.lastname@example.org), Ying Wai Li (Oak Ridge National Laboratory, email@example.com), David P Landau (University of Georgia, firstname.lastname@example.org)
Many interesting material properties can be understood and predicted by computation involving a solution of the electronic structure problem. The combination of new algorithms applied to high performance computing platforms promises a number of potential advances in the understanding of the theory of complex materials and in the analysis of new experimental work on advanced materials. Yet, solution of the electronic structure problem remains computationally challenging when the system of interest contains a large number of atoms.
Real-space numerical electronic structure methods are mathematically robust, accurate and ideally suited for contemporary massively parallel computational resources. Real space methods have successfully been applied to both ground state and excited states, especially but not only for localized systems such as nanoscale clusters. New algorithms have been developed to optimize solutions to eigenvalue problems and expedite or circumvent the computation of empty states in excited state computations.
Topics in this focus session include but are not limited to: real space or grid based methods using finite differencing, finite elements, or variations thereof; applications to large nanoscale systems, ab initio molecular dynamics, noncollinear magnetic systems, optical excitations, and molecular transport; new algorithms designed for expediting and applying these methods to state of the art computational platforms.
Organizers: Jim Chelikowsky (University of Texas at Austin, email@example.com), Leeor Kronik (Weizmann Institute, firstname.lastname@example.org), Angel Rubio (Max Planck Institute, email@example.com)
The development of predictive computational simulation for accelerating the discovery and rational design of functional materials is a challenge of great contemporary interest. Advances in algorithms and predictive power of computational techniques are playing a fundamental role in the discovery of novel functional materials, with successful examples in catalysis, batteries, and photoelectrochemistry. High-throughput computation and materials databases have recently enabled rapid screening of both molecules and solid-state compounds with multiple properties and functionalities. This focus topic will cover research efforts to accelerate materials discovery and/or development by building the fundamental knowledge base and applying novel data driven approaches to design materials with specific and targeted functional properties from first principles.
Abstracts are solicited in the areas of interest that include computational materials design and discovery; development of accessible and sustainable data infrastructure; development of new data analytic tools and statistical algorithms; advanced simulations of material properties in conjunction with new device functionality; data uncertainty quantification; advances in predictive modeling that leverage machine learning and data mining; algorithms for global structure and property optimizations; and computational modeling of materials synthesis. The technical applications include but are not limited to electronic and optoelectronic materials, magnetic materials and spintronics, energy conversion and storage materials (thermoelectrics, batteries, fuel cells, photocatalysts, photovoltaics, ferroelectrics), metallic alloys, and two-dimensional materials. Contributions that feature strong connection to experiments are of special interest.
Organizers: Kai-Ming Ho (Iowa State University, firstname.lastname@example.org), Feng Zhang (Ames Laboratory, email@example.com),Chris Wolverton (NorthwesternUniversity,firstname.lastname@example.org)
Recent advances in force fields, algorithm design, data analytics, and large scale parallel machines have stimulated great interest in modeling hard and soft materials and biological systems with molecular dynamics (MD) simulations. Multimillion-to-billion atom MD simulations with classical force fields trained by ab initio quantum mechanical (QM) simulations can reliably describe charge transfer, bond breaking/bond formation, and chemical reactions in materials under normal and extreme operating conditions. Machine learning approaches are greatly accelerating the development of quantum-mechanically informed force fields for massively parallel MD simulations. Combining coarse grained and atomistic modeling with machine learning methods enable high-throughput screening of materials. Accelerated dynamics approaches have enabled MD simulations to reach sufficiently long time scales to study rare events.
The focus session will cover a wide range of topics that include but are not limited to:
Organizers: Rajiv Kalia (University of Southern California, email@example.com), Roberto Car (Princeton University, firstname.lastname@example.org), Gary S. Grest (Sandia National Laboratory, email@example.com), Brian Barnes (Army Research Laboratory, firstname.lastname@example.org)
This focus topic covers the field of computational modeling of solid/aqueous-electrolyte interfaces. It includes but is not limited to understanding the need to accurately describe electronic charge transfer and localization in solvated ionic environments, the importance of many-body effects and non-local correlations, the role of polarization in simulations of electrolyte solutions, the level alignment at the electrochemical interface and wet semiconducting surfaces, etc. The topic is also open to experimentalists interested on understanding the fundamentals of these systems at the atomistic level.
Organizers: Marivi Fernandez-Serra (Stony Brook University, email@example.com), Luana Pedroza (Universidade Federal do ABC, Sao Paolo, BR, firstname.lastname@example.org), Alexandre Reily Rocha (IFT Sao Paulo, email@example.com)
This focus session is motivated by the surge of interest over the last five years in concentrated electrolyte materials for high-energy and high-capacity batteries. As part of the strategy to increase the battery power density and safety, materials composed of high concentrations of alkali-salt in ionic liquids and solid amorphous polymers are increasingly seen as attractive candidates to replace conventional organic electrolytes. Important technological parameters such as charge/discharge rates and efficiency of the whole battery are controlled and underpinned by the electrolyte transport properties, namely ionic conductivity and transference number. The ionic nature and high concentrations at play clearly point at the adoption of rigorous concentrated solution theory for both experimental and computational efforts dedicated at understanding the complex transport dynamics in such materials. The past year has seen a tremendous increase in interest around correlated ionic transport properties, and new effects like a negative transference number have been uncovered. Contributions to this focus session will include both computational and experimental investigations of correlated ionic transport in electrolyte materials.
Organizers: Arthur France-Lanord (Massachusetts Institute of Technology, firstname.lastname@example.org), Nicola Molinari (Harvard University, email@example.com)
van der Waals (vdW) interactions play a central role in determining the stability, structure, and function of systems throughout biology, chemistry, physics, and materials science. Arising from coupled instantaneous charge fluctuations in matter, these non-bonded interactions are quantum mechanical in nature and therefore pose a substantial challenge to both theory and experiment. This focus session will cover state-of-the-art theoretical and experimental approaches for gaining a fundamental understanding of vdW interactions in a range of systems spanning molecules (e.g., intra- and inter-molecular vdW interactions, molecular dimers and clusters), materials (e.g., molecular crystals, insulators, semiconductors, metals, surfaces), as well as complex environments (e.g., in the presence of solvent, electromagnetic fields, finite thermodynamic conditions).
Organizers: Robert A. DiStasio Jr. (Cornell University, firstname.lastname@example.org), Noa Marom (Carnegie Mellon University, email@example.com), Matthias Scheffler (Fritz Haber Institute of the Max Planck Society, firstname.lastname@example.org )
Thermal transport plays a key role in many phenomena in condensed and low-dimensional systems, and has vital implications in thermoelectric applications. Heat management is also a key technological challenge in electronic, photonic, and solar cell devices. Recent advances in materials science and device fabrication offer new opportunities for an interplay of electronic and phononic degrees of freedom, leading to complex device cooling pathways. Low-dimensional materials exhibit unique hydrodynamics often distinct from that observed in typical three-dimensional materials. Additionally, while vibrations can be considered thermal noise, single phonons could be used to carry quantum information, offering new paradigms in quantum information science and technology. Corresponding recent developments in modeling and simulation provide new opportunities to gain fundamental insights to these emerging behaviors.
This session will focus on thermal transport in the diffusive, hydrodynamic, and ballistic regimes, on interfacial thermal resistance, on quantum phononics, and on first-principles and molecular dynamics simulations of thermal conductivity and phonon drag in nanostructures, 2D materials, and bulk materials.
Organizers: Vasili Perebeinos (University of Buffalo), Elif Ertekin (University of Illinois at Urbana Champaign, email@example.com), Nicola Marzari (Ecole Polytechnique Fédérale de Lausanne, firstname.lastname@example.org )
There is currently a major push towards the realization of fault-tolerant quantum processors as well as exciting research at the quantum-advantage frontier. This focus session will highlight the technological advances towards these goals that have been achieved by one of its leading technologies: superconducting qubits. Talks will address improvements in a number of areas related to this technology. To improve qubit performance, we consider novel qubits - such as heavy-fluxonium, 0-pi and current-mirror devices - and high-fidelity gates developed and optimized on a variety of superconducting qubit architectures. To improve coherence across multiple qubits and increase the number of qubits in a device, we consider advances in modular architectures, 3D fabricating and integration, and using microwave photons to carry quantum information between processing nodes via waveguides. Talks in this session will include, but aren't limited to, these relevant topics to superconducting qubits.
Organizers: Blake Johnson, Jens Koch, Eric Lucero, David McKay
Qubits realized in semiconductors continue to make major advances in multiple materials. Spins in electrostatically defined quantum dots in both group-III-V and group-IV semiconductors, in optically-controlled self-assembled quantum dots, and bound to impurities, have all witnessed coherent control with increasing fidelity and progress in the mitigation of decoherence. Recent developments include demonstrations of quantum logic in multiple dots, the analysis of robust methods for reducing charge and hyperfine noise effects, improvements in device development and characterization, and hybridization with superconducting resonators. These developments all indicate strong progress for single and multiple coupled qubits across different semiconducting materials and control methods. This focus session is intended to draw together this progress, with interest in device fabrication, state initialization, read-out, demonstrations of coherent manipulation, and theoretical modeling.
Organizers: Thaddeus Ladd, Andrea Morello
Atoms (neutral and ionic) are natural carriers of quantum information and form the basis for many quantum technologies including digital quantum computers, analog quantum simulators, memory for quantum networks, and quantum metrological standards and sensors. This focus session will highlight various advances across a broad suite of atomic-based quantum technologies.
Organizers: Ivan Deutsch
Hybrid quantum systems consisting of a combination of distinct elements, such as superconducting and semiconducting, allow for the coupling of diverse quantum degrees of freedom, e.g. the microscopic electronic degrees of freedom (charge or spin) and cavity photons in a superconducting microwave resonator. Research in this area opens new opportunities to combine previously disconnected quantum systems such as superconducting, charge, spin, phononic and photonic qubits, and study their functionalities for qubit manipulation, quantum information processing, and quantum simulation.
Organizers: Guido Burkhard and Mark Gyure
As quantum information processors scale up, from 1 to 2 to 5 to (now) 20 or more qubits, noise and errors remain a major challenge. Unfortunately, many of the standard tools for characterizing these errors become impractical beyond two or three qubits. Further progress towards computationally useful quantum devices therefore demands new approaches to modeling, measuring, and mitigating both familiar error processes (decoherence of individual qubits) as well as emergent ones that threaten standard approaches to fault-tolerant error correction (crosstalk, leakage, correlated errors, etc.). This focus session highlights progress on characterizing this diverse spectrum of physical errors, modeling their impact, and mitigating their effects in near-term, noisy, intermediate-scale quantum devices.
Organizers: Seth Merkel, Matthew Ware, Kevin Young
The maturation of quantum information technologies highlights an opportunity for quantum control solutions to accelerate pathways to useful quantum systems. Quantum control as a focused discipline provides means for both improving system performance in the presence of noise and imperfections, and synthesizing exotic quantum states and dynamics of interest. The confluence of emerging capabilities in controlled coherent dynamics and reservoir engineering with advances in machine learning is now positioning quantum control as an enabler of a new class of exploratory physics investigations. This session will bring together theorists and experimentalists working across different quantum control areas, assess recent progress and outstanding challenges, and identify areas where control can open new capabilities in fundamental quantum physics.
Organizers: Michael Beircuk and Lorenza Viola
The field of quantum information has sometimes been called “applied quantum foundations”. This why work in the foundations of quantum mechanics finds its natural home in the Division of Quantum Information. Quantum foundations research includes all fundamental aspects of quantum entanglement, Bell inequalities, contextuality results like the Kochen-Specker theorem, complementarity, quantum measurement theory, various conundrums like Wigner’s friend, delayed choice experiments, and the like, as well as conceptual work in quantum interpretations such as Everett’s many-world interpretation and QBism.
Organizers: Matthew Leifer, Rob Spekkens, Ian Durham
Two important developments in quantum computing in recent years have made this a privileged time in the history of the field: first is computers being built with 50-100 qubits and high fidelity gates (so called NISQ computers), and the second is public access to such machines. Both of these milestones have made quantum software more important than ever.
Good software is at the heart of putting these machines to work. It allows the computation to efficiently exploit the limited resources of NISQ computers, accelerates finding useful applications for them, allows users to explore techniques for error mitigation and correction, and can reduce user error through better programming constructs and feedback. Finally, software is the entry point for cloud access quantum computers, opening up the field to thousands of new users who bring new insights and expertise.
This focus session is intended to bring together researchers working on all aspects of the quantum software stack: quantum programming languages, compilers and optimizers, software for characterizing errors and finding error correction codes, classical simulation of quantum computation, and libraries for quantum algorithms and applications. Topics may also take the form of identifying gaps in existing software stacks or possible interoperability among them. Of particular interest is to identify ways that better software can accelerate the pace towards practical quantum computation by offering greater efficiency.
Organizers: Raphael Pooser and Ali Javadi
Topological Stabilization of Memory and Computation: Encoding quantum information topologically is a powerful strategy for achieving fault-tolerant quantum computing platforms. This includes both active approaches, as utilized in topological codes, and passive approaches, achieved by manifesting topological phases of matter. Recent progress in the field has proposed synthesizing these two approaches, uncovered deep relations between them, and advanced novel methods of processing their topologically encoded quantum information. There has also been a steady exploration of new codes/phases and their properties, such as fracton phases, which can realize self-correcting quantum memory. Combined with the accelerating experimental activity on topological phases and multi-qubit systems, this is a ripe time for the study of topological quantum computing.
Organizer: Parsa Bonderson
Quantum error correction is an algorithmic way to reduce the effect of physical errors on a quantum computation by encoding quantum information into a subspace of the entire system. This focus session will highlight recent experimental advances towards quantum error correction and novel theoretical methods for developing and implementing quantum error correcting codes. Topics will vary from topological codes to bosonic codes and from fault-tolerant stabilizer measurements to symmetry protected subspaces.
Organizers: Ken Brown, Andrew Cross, Andrew Landahl
Machine learning has become a household term due to rapid advances in massively parallel processing units and the equally fast expansion in available data. More recently, we have witnessed a increased interest in applying early quantum technologies to machine learning as an addition to the heterogeneous architectures that learning algorithms already exploit. As noise levels remain high in near-term intermediate-scale quantum (NISQ) devices and scalability is also limited, the question is whether these technologies can give any kind of advantage that the machine learning community would be interested in. Much research effort has been dedicated to the application of optimization or sampling by quantum annealing, but we have also seen proposals for learning algorithms using gate-based quantum computers, continuous-variable and open quantum systems. The latest results in the field show distinct advantages in specific learning scenarios, but much more work is needed to develop algorithms for near-term quantum devices. The proposed invited session showcases some of the most interesting results and discusses major open questions.
Organizers: Antonio Corcolos-gonzalez, Frencesco Petruccione
It is anticipated that in the near-term future, Noisy Intermediate-Scale Quantum (NISQ) technologies will be available to quantum information scientists. This session explores the potential applications of such quantum computers with ~100 noisy qubits, and how they may serve as a stepping-stone toward larger scale, fault-tolerant devices of the future.
Organizers: Simon Benjamin, Pedram Roushan
With the developments of quantum technology, we are at the interesting cutting edge of performing experiments related to quantization of heat transfers, such as understanding how heat dissipates in superposition state and how it is exchanged between entangled states. Linking the physics of heat dissipation to entropy flow and the quantum notion of work indicates that we are equipped to consistently approach understanding one of the long-lasting questions in physics which is what is quantum thermodynamics. In this session we will invite some of the most interesting experimental and theretical results taken about this subject in the last year and this will help experts to establish a roadmap for research in the next year.
Organizer: Mohammad Ansari
Adiabatic quantum computing and quantum annealing are computational methods that have been proposed to solve combinatorial optimization and sampling problems. They have recently been successfully extended to include quantum simulation. Several efforts are underway to manufacture processors that implement these strategies, representing the largest integrated quantum information processing available to date. This session will expose the Physics community to some of the latest results in this exciting and rapidly developing field.
Organizers: Richard Harris, Daniel Lidar
Quantum networks form an integral part of quantum technologies, posing significant challenges to science and engineering. On the one hand, quantum networks at short distances promise a path towards scalability of quantum computing systems in which multiple smaller quantum computers are connected into one larger quantum computing cluster. On the other hand, quantum networks at large distances, i.e. a quantum internet, offer a host of new applications such as for example quantum secure communication. The objective of this session is to discuss advancements and challenges in the realization and application of networked quantum technologies. This includes all aspects involved in networked quantum computing and communication systems, ranging from theoretical designs and experimental implementations, all the way to the development of quantum algorithms and protocols for quantum networks.
Organizers: Charles Bennett and Stephanie Wehner
Today is an exciting time in quantum metrology and measurements of individual quantum systems. Theorists are challenging long-held beliefs and assumptions, ranging from the true limits of resolution (e.g. the Rayleigh criterion), to the proper counting of resources and ultimate achievability of bounds. Inspired by error suppression techniques in quantum computing, they are also finding new avenues to achieve these bounds despite the presence of loss and noise. Experimental work has been no less exciting: quantum-limited measurements are now being made on larger and larger systems, including superconducting circuits and quantum optomechanical systems. Experiments have investigated spin squeezed magnetometry, adaptive phase measurements in qubits and the possibility of quantum-enhanced dark matter searches. This session will provide a forum for discussing the most recent theoretical and experimental results related to quantum measurement, metrology and sensing, as well as provide a venue for discussing future research directions.
Organizers: Aashish Clerk and Konrad Lenhert
Measurements on quantum systems are at the heart of every quantum physics course and absolutely key for either processing quantum information (error correction) or controlling quantum systems (feedback). The advent of experiments on quantum computing systems has triggered a new wave of research on the topic of measuring the state of qubits with increasing speed and fidelity, while retaining an ideally non-demolition measurement process; for example, one that does not change the state of the qubit. Understanding the tradeoffs surrounding control and measurement, along with maintaining high coherence, can be drivers for developing new methods that make for good quantum computing systems. This session will address the experimental and theoretical progress made in measurements of qubits, focusing on systems of quantum dot qubits, superconducting qubits, and other hybrid systems.
Organizer: Danny Kim
The behavior of matter under extreme conditions of high pressure, temperature, strain and strain rate is of fundamental scientific importance. Geophysical processes in the core of the Earth and other planets, matter withstanding hypervelocity impacts of comets, shock wave compression of materials, detonation of explosives, high pressure and high temperature synthesis of novel materials, failure of materials reaching their intrinsic limit of performance, all require an understanding of the fundamental mechanisms of materials response at the atomic, microstructural, and continuum levels. The advent of x-ray free electron lasers (XFELs), 3rd-4th generation synchrotron sources, and static and dynamic compression facilities in the US (NIF, APS/ANL, LCLS/SLAC) and elsewhere (European XFEL, SACLA, ESRF) as well as recent advances in theory and modeling open up new exciting opportunities for successful collaborations between experiment and theory/simulations.
This focus session, consisting of several invited and contributed talks, will assess recent experimental and computational efforts towards exploring the fundamental properties of materials at extreme conditions, including:
(1) high-pressure and high temperature synthesis and characterization of materials;
(2) static high pressure and shock-induced materials behavior, including plasticity, phase transitions, and chemical reactions;
(3) high strain rate phenomena occurring upon ultrafast energy deposition;
(4) static and dynamic properties of energetic materials, including structural stability at high P-T conditions, P-T phase diagrams, and detonation phenomena;
(5) properties of matter in the warm dense regime;
(6) new computational methods including development of interatomic potentials, multi-scale simulations, techniques for reaching longer timescales, and novel applications of data science and exascale computations to simulate matter at extreme conditions.
Organizers: Ivan Oleynik (University of South Florida, email@example.com) Cindy Bolme (Los Alamos National Laboratory, firstname.lastname@example.org), Nenad Velisavljevic (Advanced Photon Source at Argonne National Laboratory, HPCAT-Director@anl.gov), Tim Germann (Los Alamos National Laboratory, email@example.com)
The success of deep learning approaches in the analysis of images and movies is starting to impact a wide range of research areas in physics. The goal of this focus session is to share best practices in deep learning for computer vision as applied across the physics research areas represented at the APS March Meeting, in particular, biophysics, soft matter physics, and statistical and nonlinear physics. Both new approaches to deep learning and adaptation and implementation of existing deep learning tools are of interest for this focus session.
Organizers: Wolfgang Losert (University of Maryland, firstname.lastname@example.org)
This session will focus on physics models, in-vivo measurement systems, and energy delivery systems that enable advanced medical devices for therapy and surgery. Advanced medical devices increasingly rely on accurate complex multi-physics models. Examples include MRI-Linac systems which combine real time imaging with dynamically controlled radiation dosing, magnetic resonance guided high-intensity focused ultrasound therapy, imaging systems integrated with robotics and virtual reality systems, photoacoustic systems, deep brain stimulation, transcranial magnetic stimulation, and low cost dynamically reconfigurable MEMS based ultrasound systems. With this new generation of advanced medical devices, there is a critical need for physicists to develop and validate multi-physics models that include multiple simultaneous in-vivo processes such as radiation induced tissue damage, magnetic resonance, low frequency electromagnetic stimulation, photonics, and acoustics. Here we invite contributed abstracts on research that will provide innovative ideas to validate and enable the next generation of medical devices.
Organizers: Stephen Russek (NIST, email@example.com), Ron Goldfarb (NIST, firstname.lastname@example.org)
This session invites abstracts on both physics-based (derived from fundamental principles) and statistics-based (derived from statistical analysis of clinical data) models developed to improve our understanding of healthy physiology, disease, and therapy. Computational approaches directly supported with real-world data are particularly encouraged. General, population-level models of all stages of the disease development (e.g., disease onset, disease progression), as well as models of therapeutic interventions and their impact on disease in different disease settings (e.g., oncology, neurodegenerative disorders, cardiology) are appropriate. Patient-specific models based on biomarkers (e.g., imaging, molecular biomarkers), that can allow prognostic and predictive connection to the outcome data (e.g., post therapy) are similarly appropriate.
Organizers: Robert Jeraj (University of Wisconsin, email@example.com), Robert H Austin (Princeton University, firstname.lastname@example.org)
Progress in the field of medical optics is driven by development of new light sources, optical detectors, and analysis algorithms, resulting in faster, more sensitive, smaller and less expensive optical systems more suitable for the clinical environment. The session objectives are to provide a review of recent developments, to report novel approaches, and to bring together the clinical, research, and industrial communities advancing the field of medical optics.
The session topics include applications in medical diagnostics and therapy, for example: o optical spectroscopy (Raman, VIS-NIR, fluorescence spectroscopy), o optical imaging (OCT, photoacoustic tomography, spectral imaging), o optical microscopy (confocal, multiphoton, FLIM) o laser therapy (dermatology, gynecology, dentistry, ophthalmology) o photodynamic therapy o photobiomodulation therapy o quantum biometrology
Organizers: Matija Milanic (University of Ljubljana, email@example.com), Stephen Russek (NIST, firstname.lastname@example.org)