Latest in cond-mat.soft

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On mean-field theories of dynamics in supercooled liquidsJun 13 2019We develop a hybrid numerical approach to extract the exact memory function K(t) of a tagged particle in three-dimensional glass-forming liquids. We compare the behavior of the exact memory kernel to two mean-field approaches, namely the standard mode-coupling ... More
The effect of confinement on the solid-liquid transition in a core-softened potential systemJun 13 2019We present a comparative computer simulation study of the phase diagrams and anomalous behavior of two-dimensional ($2D$) and quasi-two-dimensional ($q2D$) classical particles interacting with each other through isotropic core-softened potential which ... More
The hydrophobic effect characterises the thermodynamic signature of amyloid fibril growthJun 13 2019Many proteins have the potential to aggregate into amyloid fibrils, which are associated with a wide range of human disorders including Alzheimer's and Parkinson's disease. In contrast to that of folded proteins, the thermodynamic stability of amyloid ... More
Dry, aligning, dilute, active matter: A synthetic and self-contained overviewJun 13 2019These notes are based on lectures given during the Summer School `Active Matter and Nonequilibrium Statistical Physics', held in Les Houches in September 2018. Dry, aligning, dilute, active matter (DADAM), with its many adjectives, refers to a corner ... More
Entropic elasticity and negative thermal expansion in a simple cubic crystalJun 12 2019While most solids expand when heated, some materials show the opposite behavior: negative thermal expansion (NTE). In polymers and biomolecules, NTE originates from the entropic elasticity of an ideal, freely-jointed chain. The origin of NTE in solids ... More
Event-chain Monte Carlo simulations of the liquid to solid transition of two-dimensional decagonal colloidal quasicrystalsJun 12 2019In event-chain Monte Carlo simulations we model colloidal particles in two dimensions that interact according to an isotropic short-ranged pair potential which supports the two typical length scales present in decagonal quasicrystals. We investigate the ... More
Mechanics of allostery: contrasting the induced fit and population shift scenariosJun 12 2019In allosteric proteins, binding a ligand can affect function at a distant location, for example by changing the binding affinity of a substrate at the active site. The induced fit and population shift models, which differ by the assumed number of stable ... More
In silico evidence that protein unfolding is as a precursor of the protein aggregationJun 12 2019We present a computational study on the folding and aggregation of proteins in aqueous environment, as function of its concentration. We show how the increase of the concentration of individual protein species can induce a partial unfolding of the native ... More
Swelling thermodynamics and phase transitions of polymer gelsJun 12 2019We present a pedagogical review of the swelling thermodynamics and phase transitions of polymer gels. In particular, we discuss how features of the volume phase transition of the gel's osmotic equilibrium is analogous to other transitions described by ... More
Continuous to intermittent flows in growing granular heapsJun 12 2019If a granular material is poured from above on a horizontal surface between two parallel, vertical plates, a sand heap grows in time. For small piles, the grains flow smoothly downhill, but after a critical pile size $x_c$, the flow becomes intermittent: ... More
Relating microswimmer synthesis to rheotactic tunabilityJun 11 2019We explore the behavior of micron-scale autophoretic Janus (Au/Pt) rods, having various Au/Pt length ratios, swimming near a wall in an imposed background flow. We find that their ability to robustly orient and move upstream, i.e. to rheotax, depends ... More
Displacements representations for the problems with spherical and circular material surfaces with surface tensionJun 11 2019The displacements representations of the type used by Christensen and Lo (1979) are modified to allow for analytical treatment of problems involving spherical and circular material surfaces that possess constant surface tension. The modified representations ... More
Phase CrystalsJun 11 2019Superconducting order owes its properties to broken symmetry of the U (1) phase. In the presence of competing orders, or in pairbreaking environments, usual superconductivity may give way to modified condensates. Here we describe one such alternative, ... More
Formation of structure for gas-liquid, non-equilibrium polymer mediaJun 11 2019This paper examines the mechanisms of destruction and synthesis for macromolecules, which may be propelled by external acoustic fields in the flows of polymeric liquids containing a large number of gas bubbles. The dynamics of these bubbles is assumed ... More
Universal scaling of active nematic turbulenceJun 11 2019A landmark of turbulence is the emergence of universal scaling laws, such as Kolmogorov's $E(q)\sim q^{-5/3}$ scaling of the kinetic energy spectrum of inertial turbulence with the wave vector $q$. In recent years, active fluids have been shown to exhibit ... More
Geometric localization in supported elastic strutsJun 11 2019Localized deformation patterns are a common motif in morphogenesis and are increasingly finding widespread applications in materials science, for instance as memory devices. Here we describe the emergence of spatially localized deformations in a minimal ... More
Biomimetic Polymer Film with Brilliant Brightness Using a One-Step Water Vapor-Induced Phase Separation MethodJun 11 2019The scales of the white Cyphochilus beetles are endowed with unusual whiteness arising from the exceptional scattering efficiency of their disordered ultrastructure optimized through millions of years of evolution. Here, a simple, one-step method based ... More
Generalized Lorentz reciprocal theorem in complex fluids and in non-isothermal systemsJun 11 2019The classical Lorentz reciprocal theorem (LRT) was originally derived for slow viscous flows of incompressible Newtonian fluids under the isothermal condition. In the present work, we extend the LRT from simple to complex fluids with open or moving boundaries ... More
Linking morphology and thermal transport of asymmetric polymer blends by maromolecular engineeringJun 10 2019A grand challenge in designing polymeric materials is to tune their properties by macromolecular engineering. In this context, one of the drawbacks that often limits broader applications under high temperature conditions is their poor thermal conductivity ... More
Chain Flexibility and the Segmental Dynamics of PolymersJun 10 2019Using molecular dynamics simulations we examine the dynamics of a family of model polymers with varying chain length and torsional potential barriers. We focus on features of the dynamics of polymers that are seen experimentally but absent in simulations ... More
Geometric evolution as a source of discontinuous behavior in soft condensed matterJun 10 2019Geometric evolution represents a fundamental aspect of many physical phenomena. In this paper we consider the geometric evolution of structures that undergo topological changes. Topological changes occur when the shape of an object evolves such that it ... More
Rheology of bacterial suspensions under confinementJun 10 2019As a paradigmatic model of active fluids, bacterial suspensions show intriguing rheological responses drastically different from their counterpart colloidal suspensions. Although the flow of bulk bacterial suspensions has been extensively studied, the ... More
Command of Collective Dynamics by Topological Defects in Spherical CrystalsJun 10 2019Directing individual motions of many constituents to coherent dynamical state is a fundamental challenge in multiple fields. Here, based on the spherical crystal model, we show that topological defects in particle arrays can be a crucial element in regulating ... More
Three-Dimensional Yielding in Anisotropic Materials: Validation of Hill CriterionJun 10 2019Yielding transition in isotropic soft materials under superposition of orthogonal deformation fields is known to follow von Mises criterion. However, in anisotropic soft materials von Mises criterion fails owing to preferred directions associated with ... More
Active glassesJun 09 2019Active glassy matter has recently emerged as a novel class of non-equilibrium soft matter, combining energy-driven, active particle movement with dense and disordered glass-like behavior. Here we review the state-of-the-art in this field from an experimental, ... More
Compact Group Approach to the Analysis of Dielectric and Optical Characteristics of Finely Dispersed Systems and LiquidsJun 09 2019We present the compact group approach to analysis of the long-wavelength dielectric and optical characteristics of substances which can be modeled as macroscopically homogeneous and isotropic systems of hard dielectric particles embedded into a dielectric ... More
Landau theory for smectic-A -- hexatic-B coexistence in smectic filmsJun 09 2019We explain theoretically peculiarities of the smectic A -- hexatic B equilibrium phase coexistence in a finite temperature range recently observed experimentally in free standing smectic films [I.A.Zaluzhnyy et al., Physical Review E, volume 98, 052703 ... More
Self-organisation of tip functionalised elongated colloidal particlesJun 08 2019Weakly attractive interactions between the tips of rod-like colloidal particles affect their liquid-crystal phase behaviour due to a subtle interplay between enthalpy and entropy. Here, we employ molecular dynamics simulations on semi-flexible, repulsive ... More
Brittle-Ductile Transition in a Metallic GlassJun 08 2019Recent computational and laboratory experiments have shown that the brittle-ductile transition in metallic glasses such as Vitreloy-1 is strongly sensitive to the initial effective disorder (or ``fictive'') temperature. Glasses with lower effective temperatures ... More
Shear viscosity of pseudo hard-spheresJun 08 2019We present molecular dynamics simulations of pseudo hard sphere fluid (generalized WCA potential with exponents (50, 49) proposed by Jover et al. J. Chem. Phys 137, (2012)) using GROMACS package. The equation of state and radial distribution functions ... More
Kinetic theory based segregation model for density-bidisperse dense granular flowsJun 08 2019Individual constituent balance equations are often used to derive expressions for species specific segregation velocities in flows of dense granular mixtures. We propose an expression for the interspecies momentum exchange in density bidisperse granular ... More
Effect of electric field on water diffusion in carbon nanotubesJun 07 2019We investigate the diffusion and structure of TIP4P/2005 water confined in carbon nanotubes under the effect of electric field. For nanotubes with distinct diameters we vary the intensity and the direction of the electric field. We show that the nanotube ... More
Modified Archimedes' principle predicts rising and sinking of intruders in sheared granular flowsJun 07 2019We computationally determine the force on single spherical intruder particles in sheared granular flows as a function of particle size, particle density, shear rate, overburden pressure, and gravitational acceleration. The force scales similarly to, but ... More
Ground States of Crystalline Caps: Generalized Jellium on Curved SpaceJun 07 2019Jun 11 2019We study the structure and elastic energy of the ground states of crystalline caps conforming to a spherical surface. These ground states consist of positive disclination defects in structures spanning from flat and weakly curved crystals to closed shells. ... More
Harnessing elasticity to generate self-oscillation via an electrohydrodynamic instabilityJun 07 2019Under a steady DC electric field of sufficient strength, a weakly conducting dielectric sphere in a dielectric solvent with higher conductivity can undergo spontaneous spinning (Quincke rotation) through a pitchfork bifurcation. We design an object composed ... More
A comparative study between two models of active cluster-crystalsJun 07 2019We study a system of active particles with soft repulsive interactions that lead to an active cluster-crystal phase. We use two different modelizations of the active force - Active Brownian particles (ABP) and Ornstein-Uhlenbeck particles (AOUP) - and ... More
Shear-induced contact area anisotropy explained by a fracture mechanics modelJun 07 2019This paper gives a theoretical analysis for the fundamental problem of anisotropy induced by shear forces onan adhesive contact, discussing the experimental data of the companion Letter. We present a fracture mechanicsmodel where two phenomenological ... More
On the decay of the pair correlation function and the line of vanishing excess isothermal compressibility in simple fluidsJun 07 2019We re-visit the competition between attractive and repulsive interparticle forces in simple fluids and how this governs and connects the macroscopic phase behavior and structural properties as manifest in pair correlation functions. We focus on the asymptotic ... More
Shear-Induced Anisotropy in Rough Elastomer ContactJun 07 2019True contact between randomly rough solids consists of myriad individual micro-junctions. While their total area controls the adhesive friction force of the interface, other macroscopic features, including viscoelastic friction, wear, stiffness and electric ... More
Lectures on non-equilibrium active systemsJun 07 2019These notes are based on lectures given during the Summer School `Active matter and non-equilibrium statistical physics', held in Les Houches in September 2018. In these notes, we have merged our lectures into a single chapter broadly dedicated to `Non-equilibrium ... More
Phase diagram of helicoids in Chiral Liquid CrystalsJun 06 2019Cholesteric Liquid Crystals (CLCs), in presence of an external uniform electric field and confined between two parallel planes with strong homeotropic anchoring conditions, are found to admit different types of helicoidal solutions with disclinations. ... More
Phase diagram of helicoids in Chiral Liquid CrystalsJun 06 2019Jun 10 2019Cholesteric Liquid Crystals (CLCs), in presence of an external uniform electric field and confined between two parallel planes with strong homeotropic anchoring conditions, are found to admit different types of helicoidal solutions with disclinations. ... More
A phase inversion benchmark for multiscale multiphase flowsJun 06 2019A series of benchmarks based on the physical situation of "phase inversion" between two incompressible liquids is presented. These benchmarks aim at progressing toward the direct numerical simulation of two-phase flows. Several CFD codes developed in ... More
Foldable Cones as a Framework for Nonrigid OrigamiJun 06 2019The study of origami-based mechanical metamaterials usually focuses on the kinematics of deployable structures made of an assembly of rigid flat plates connected by hinges. When the elastic response of each panel is taken into account, novel behaviors ... More
Signatures of Physical Aging and Thixotropy in Aqueous Dispersion of CarbopolJun 06 2019In this work, we investigate signatures of physical aging in an aqueous dispersion of Carbopol that shows yield stress and weak enhancement in elastic modulus as a function of time. We observe that the creep curves, as well as strain recovery, show a ... More
Patterns of polar domains in a spatiotemporal model of interacting polaritiesJun 06 2019Polarity fields are known to exhibit long distance patterns, in both physical and biological systems. The mechanisms behind such patterns are poorly understood. Here, we describe the dynamics of polarity fields using an original physical model that generalizes ... More
Model of lamellipodium initiation during cell spreadingJun 06 2019Cell spreading requires a major reorganisation of the actin cytoskeleton, from a cortical structure to a lamellipodium where filaments are mostly parallel to the substrate. We propose a model inspired by the physics of nematic liquid crystals and fluid ... More
Coherence and Interaction in confined room-temperature polariton condensates with Frenkel excitonsJun 06 2019The strong light-matter coupling of a microcavity mode to tightly bound Frenkel excitons in organic materials emerged as a versatile, room-temperature compatible platform to study nonlinear many-particle physics and bosonic condensation. However, various ... More
Cup-to-vesicle transition of a fluid membrane with spontaneous curvatureJun 06 2019The disk-to-vesicle transition of a fluid membrane with no spontaneous curvature is well described by the competition between edge line and curvature energies. However, the transition of asymmetric membranes with spontaneous curvatures is not yet understood. ... More
Random sequential adsorption of Platonic and Archimedean solidsJun 05 2019The aim of the study presented here was the analysis of packings generated according to random sequential adsorption protocol consisting of identical Platonic and Archimedean solids. The computer simulations performed showed, that the highest saturated ... More
Induced correlations and rupture of molecular chaos by anisotropic dissipative Janus hard disksJun 05 2019A system of smooth "frozen" Janus-type disks is studied. Such disks cannot rotate and are divided by their diameter into two sides of different inelasticities. Taking as a reference a system of colored elastic disks, we find differences in the behavior ... More
Curvature-driven wrinkling of thin elastic shellsJun 05 2019How much energy does it take to stamp a thin elastic shell flat? Motivated by recent experiments on the wrinkling patterns formed by thin shells floating on a water bath, we develop a rigorous method via $\Gamma$-convergence for answering this question ... More
Force transmission and the order parameter of shear thickeningJun 05 2019The origin of the abrupt shear thickening observed in some dense suspensions has been recently argued to be a transition from frictionless (lubricated) to frictional interactions between immersed particles. The Wyart-Cates rheological model, built on ... More
Surface permeability and surface flow tortuosity of particulate porous mediaJun 05 2019The dispersion process in particulate porous media at low saturation levels takes place over the surface elements of constituent particles and, as we have found previously by comparison with experiments, can be accurately described by super-fast non-linear ... More
Propulsion driven by self-oscillation via an electrohydrodynamic instabilityJun 05 2019Oscillations of flagella and cilia play an important role in biology, which motivates the idea of functional mimicry as part of bio-inspired applications. Nevertheless, it still remains challenging to drive their artificial counterparts to oscillate via ... More
Bifurcation dynamics of a particle-encapsulating droplet in shear flowJun 05 2019To understand the behavior of composite fluid particles such as nucleated cells and double-emulsions in flow, we study a finite-size particle encapsulated in a deforming droplet under shear flow as a model system. In addition to its concentric particle-droplet ... More
Composition and Resolution Dependence of Effective Coarse-Graining Potentials in Multi-Resolution SimulationsJun 05 2019Given that the physical properties of polymeric liquids extend on a wide range of lengthscales, it is computationally convenient to represent them by coarse-grained (CG) descriptions at various granularities to investigate local and global properties ... More
Using deformable particles for single particle measurements of velocity gradient tensorsJun 04 2019We measure the deformation of particles made of several slender arms in a two-dimensional (2D) linear shear and a three-dimensional (3D) turbulent flow. We show how these measurements of arm deformations along with the rotation rate of the particle allow ... More
Landau theory of 'bending-to-stretching` transitionJun 04 2019Transition from bending-dominated to stretching-dominated elastic response in semi-flexible fibrous networks plays an important role in the mechanical behavior of cells and tissues and its understanding is crucial for the design of new meta-materials. ... More
Landau theory of bending-to-stretching transitionJun 04 2019Jun 11 2019Transition from bending-dominated to stretching-dominated elastic response in semi-flexible fibrous networks plays an important role in the mechanical behavior of cells and tissues and its understanding is crucial for the design of new meta-materials. ... More
Design and applications of a fluorescent labeling technique for lipid and surfactant preformed vesiclesJun 04 2019Amphiphilic molecules such as surfactants, lipids and block copolymers can be assembled into bilayers and form vesicles. Fluorescent membrane labeling methods require the use of dye molecules that can be inserted in the bilayers at different stages of ... More
Kinetically constrained model for gravity-driven granular flow and cloggingJun 04 2019We add extreme driving to the Kob-Andersen kinetically-constrained lattice-gas model in order to mimic the effect of gravity on dense granular systems. For low particle densities, the current that develops in the system agrees at arbitrary field intensity ... More
The Role of Pressure in Inverse Design for AssemblyJun 04 2019Isotropic pairwise interactions that promote the self assembly of complex particle morphologies have been discovered by inverse design strategies derived from the molecular coarse-graining literature. While such approaches provide an avenue to reproduce ... More
Chaos and mixing in self-propelled dropletsJun 04 2019We consider self-propelled droplets which are driven by internal flow. Tracer particles, which are advected by the flow, in general follow chaotic trajectories, even though the motion of the autonomous swimmer is completely regular. The flow is mixing, ... More
Interface-resolved simulations of small inertial particles in turbulent channel flowJun 04 2019We present a direct comparison between interface-resolved and one-way-coupled point-particle direct numerical simulations (DNS) of gravity-free turbulent channel flow of small inertial particles, with high particle-to-fluid density ratio and diameter ... More
Precursor of a magnetic-field-induced liquid-liquid transition of oxygenJun 04 2019The acoustic properties of liquid oxygen have been studied up to 90 T by means of the ultrasound pulse-echo technique. A monotonic decrease of the sound velocity and an asymptotic increase of the acoustic attenuation are observed by applying magnetic ... More
Surface Fluctuating Hydrodynamics Methods for the Drift-Diffusion Dynamics of Particles and Microstructures within Curved Fluid InterfacesJun 04 2019We introduce fluctuating hydrodynamics approaches on surfaces for capturing the drift-diffusion dynamics of particles and microstructures immersed within curved fluid interfaces of spherical shape. We take into account the interfacial hydrodynamic coupling, ... More
Lattice Boltzmann Methods and Active FluidsJun 03 2019We review the state of the art of active fluids with particular attention to hydrodynamic continuous models and to the use of Lattice Boltzmann Methods (LBM) in this field. We present the thermodynamics of active fluids, in terms of liquid crystals modelling ... More
Polyelectrolyte solution under spatial and dielectric confinementJun 03 2019Polyelectrolytes under confinement are crucial for energy storage and for understanding biomolecular functions. Using molecular dynamics simulations, we analyze a polyelectrolyte solution confined between two oppositely charged planar dielectric surfaces ... More
Attractive vs. truncated repulsive supercooled liquids : dynamics is encoded in the pair correlation functionJun 03 2019We compare glassy dynamics in two liquids that differ in the form of their interaction potentials. Both systems have the same repulsive interactions but one has also an attractive part in the potential. These two systems exhibit very different dynamics ... More
Modelling double emulsion formation in planar flow-focusing microchannelsJun 03 2019Double emulsion formation in a hierarchical flow-focusing channel is systematically investigated using a free energy ternary lattice Boltzmann model. A three dimensional formation regime diagram is constructed based on the weber number of the inner phase ... More
Interface repulsion and lamellar structures in thin films of homopolymer blends due to thermal oscillationsJun 03 2019In equilibrium the interface potential that describes the interaction between two AB interfaces ina binary blend of A and B homopolymers is attractive at all distances, resulting in coarsening of theblend morphology even in the absence of interface curvature. ... More
Influence of Initial Residual Stress on Growth and Pattern Creation for a Layered AortaJun 03 2019Residual stress is ubiquitous and indispensable in most biological and artificial materials, where it sustains and optimizes many biological and functional mechanisms. The theory of volume growth, starting from a stress-free initial state, is widely used ... More
Computational Investigation of Ion Transport and Selectivity in a Nanoporous Desalination Membrane using Advanced Sampling TechniquesJun 03 2019The ability of semipermeable membranes to selectively impede the transport of undesirable solutes is key to many applications, including water desalination and chemical separation. Yet, the relationship between a membrane's structure and its selectivity ... More
Étude théorique de l'instabilité de formation des rides éoliennesJun 03 2019The link between external flow and granular media is investigated in view of better understanding the formation of aeolian sand ripples. The study is performed using a simplified, statistical, model based on numerical results obtained elsewhere by O. ... More
The behaviour of information flow near criticalityJun 03 2019Recent experiments have indicated that many biological systems self-organise near their critical point, which hints at a common design principle. While it has been suggested that information transmission is optimized near the critical point, it remains ... More
Theory for diffusive and ballistic air leakage and its application to suction cupsJun 03 2019We have developed a theory of air leakage at interfaces between two elastic solids with application to suction cups in contact with randomly rough surfaces. We present an equation for the airflow in narrow constrictions which interpolate between the diffusive ... More
Can the temperature of a freezing liquid increase?Jun 03 2019In this study, identical experiments of bottom-cooled solidification of water-23 wt% KNO3 and water-24 wt% NH4Cl, which exhibit faceted and dendritic microstructures respectively, were performed. The primary objective of this investigation is to understand ... More
Loopy Lévy flights enhance tracer diffusion in active suspensionsJun 03 2019Brownian motion is widely used as a paradigmatic model of diffusion in equilibrium media throughout the physical, chemical, and biological sciences. However, many real world systems, particularly biological ones, are intrinsically out-of-equilibrium due ... More
Shear induced migration of microswimmers in pressure-driven channel flowJun 03 2019We study the shear induced migration of microswimmers (primarily, active Brownian particles or ABP's) in a plane Poiseuille flow. For wide channels characterized by $U_b/HD_r \ll 1$, the separation between time scales characterizing the swimmer orientation ... More
Fully developed and transient concentration profiles of particulate suspensions sheared in a cylindrical CouetteJun 02 2019We experimentally investigate particle migration in a non-Brownian suspension sheared in a Taylor-Couette configuration and in the limit of vanishing Reynolds number. Highly resolved index-matching techniques are used to measure the local particulate ... More
Population stability risks and biophysical benefits of cell-cell fusion in macrophage, osteoclast, and giant multinucleated cellsJun 02 2019Plant and animal cells are commonly understood as acquiring specialized functions through differentiation and asymmetric division. However, unique capabilities are also acquired when two or more cells fuse together, mixing cytoplasmic and genetic material. ... More
Comparison of Shear and Compression Jammed Packings of Frictional DisksJun 02 2019We compare the structural and mechanical properties of mechanically stable (MS) packings of frictional disks in two spatial dimensions (2D) generated with isotropic compression and simple shear protocols from discrete element modeling (DEM) simulations. ... More
Deformation and dynamics of erythrocytes govern their traversal through microfluidic devices with a deterministic lateral displacement architectureJun 02 2019Deterministic lateral displacement (DLD) microfluidic devices promise versatile and precise processing of biological samples. However, this prospect has been realized so far only for rigid spherical particles and remains limited for biological cells due ... More
Self-powered shape-transforming membranes: an active matter approach to soft roboticsJun 02 2019We present the first example of an autonomous, extended, shape-transforming sheet made from a gel that shrinks and swells in response to the Belousov-Zhabotinsky (BZ) reaction. BZ waves traveling within the gel induce periodic flapping of the sheets. ... More
Analytical theory of enhanced logarithmic Rayleigh scattering in amorphous solidsJun 02 2019The damping or attenuation coefficient of sound waves in solids due to impurities scales with the wavevector to the fourth power, also known as Rayleigh scattering. In amorphous solids, Rayleigh scattering may be enhanced by a logarithmic factor although ... More
Programming Soft Robots with Flexible Mechanical MetamaterialsJun 01 2019The complex behavior of highly deformable mechanical metamaterials can substantially enhance the performance of soft robots.
A particle-field representation unifies paradigms in active matterJun 01 2019Active matter research focuses on the emergent behavior among interacting self-propelled particles. Unification of seemingly disconnected paradigms -- active phase-separation of repulsive discs and collective motion of self-propelled rods -- is a major ... More
Optical tweezers microrheology maps the dynamics of strain-induced local inhomogeneities in entangled polymersJun 01 2019Optical tweezers microrheology (OTM) offers a powerful approach to probe the nonlinear response of complex soft matter systems, such as networks of entangled polymers, over wide-ranging spatiotemporal scales. OTM can also uniquely characterize the microstructural ... More
The stability-limit conjecture revisitedMay 31 2019The stability-limit conjecture (SLC) proposes that the liquid spinodal of water returns to positive pressure in the supercooled region, and that the apparent divergence of water's thermodynamic response functions as temperature decreases are explained ... More
Surface tension of supercooled water nanodroplets from computer simulationsMay 31 2019We estimate the liquid-vapour surface tension from simulations of TIP4P/2005 water nanodroplets of size $N$=100 to 2880 molecules over a temperature $T$ range of 180 K to 300 K. We compute the planar surface tension $\gamma_p$, the curvature-dependent ... More
Mesoscopic non-equilibrium measures can reveal intrinsic features of the active drivingMay 31 2019Biological assemblies such as chromosomes, membranes, and the cytoskeleton are driven out of equilibrium at the nanoscale by enzymatic activity and molecular motors. Similar non-equilibrium dynamics can be realized in synthetic systems, such as chemically ... More
Low-frequency excitations and their localization properties in glassesMay 31 2019Besides the dynamical slowing down signaled by an enormous increase of the viscosity approaching the glass transition, structural glasses show also interesting anomalous thermodynamic features at low temperatures that hint peculiar deviations from Debye's ... More
Long-wavelength fluctuations and anomalous dynamics in two-dimensional liquidsMay 31 2019Long-wavelength Mermin-Wagner fluctuations prevent the existence of translational long-range order, in two-dimensional systems at finite temperature. Their dynamical signature, which is the divergence of the vibrational amplitude with the system size, ... More
Tuning Water Slip Behavior in Nanochannels using Self-Assembled MonolayersMay 31 2019Water slip at solid surfaces is important for a wide range of micro/nano-fluidic applications. While it is known that water slip behavior depends on surface functionalization, how it impacts the molecular level dynamics and mass transport at the interface ... More
Many-Chain Effect on the Co-nonsolvency Behavior of Polymer Brush in a Good Solvent MixtureMay 31 2019The polymer brush normally swells in a good solvent, while it collapses in a poor solvent. An abnormal response of polymer brush, so-called co-nonsolvency, is a phenomenon where the brush collapses counter-intuitively in a good solvent mixture. In this ... More
Compressing $Θ$-chain in slit geometryMay 31 2019When compressed in a slit of width $D$, a $\Theta$-chain that displays the scaling of size $R_0$ (diameter) with respect to the number of monomers $N$, $R_0\sim aN^{1/2}$, expands in the lateral direction as $R_{\parallel}\sim a N^{\nu}(a/D)^{2\nu-1}$. ... More
Current enhancement in solid-state nanopores depends on three-dimensional DNA structureMay 31 2019The translocation of double-stranded DNA through a solid-state nanopore may either decrease or increase the ionic current depending on the ionic concentration of the surrounding solution. Below a certain crossover ionic concentration, the current change ... More
Morphology and Kinetics of Random Sequential Adsorption of Superballs: From Hexapods to CubesMay 30 2019Superballs represent a class of particles whose shapes are defined by ${|x|}^{2p}+{|y|}^{2p}+{|z|}^{2p} \le R^{2p}$, with $p\in(0,\infty)$ being the "deformation parameter". $0<p<0.5$ represents a family of hexapodlike (concave octahedrallike) particles, ... More
Dynamics of a Grain-Scale Intruder in a 2D Granular Medium with and without Basal FrictionMay 30 2019We report on a series of experiments in which a grain-sized intruder is pulled by a spring through a 2D granular material comprised of photoelastic disks in a Couette geometry. We study the intruder dynamics as a function of packing fraction for two types ... More