1
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Melio J, Henkes SE, Kraft DJ. Soft and Stiff Normal Modes in Floppy Colloidal Square Lattices. PHYSICAL REVIEW LETTERS 2024; 132:078202. [PMID: 38427878 DOI: 10.1103/physrevlett.132.078202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 11/08/2023] [Accepted: 01/03/2024] [Indexed: 03/03/2024]
Abstract
Floppy microscale spring networks are widely studied in theory and simulations, but no well-controlled experimental system currently exists. Here, we show that square lattices consisting of colloid-supported lipid bilayers functionalized with DNA linkers act as microscale floppy spring networks. We extract their normal modes by inverting the particle displacement correlation matrix, showing the emergence of a spectrum of soft modes with low effective stiffness in addition to stiff modes that derive from linker interactions. Evaluation of the softest mode, a uniform shear mode, reveals that shear stiffness decreases with lattice size. Experiments match well with Brownian particle simulations, and we develop a theoretical description based on mapping interactions onto a linear response model to describe the modes. Our results reveal the importance of entropic steric effects and can be used for developing reconfigurable materials at the colloidal length scale.
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Affiliation(s)
- Julio Melio
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - Silke E Henkes
- Lorentz Institute, Leiden University, P.O. Box 9506, 2300 RA Leiden, The Netherlands
| | - Daniela J Kraft
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
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2
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Xie Z, Atherton TJ. Jamming on convex deformable surfaces. SOFT MATTER 2024; 20:1070-1078. [PMID: 38206105 DOI: 10.1039/d2sm01608g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Jamming is a fundamental transition that governs the behavior of particulate media, including sand, foams and dense suspensions. Upon compression, such media change from freely flowing to a disordered, marginally stable solid that exhibits non-Hookean elasticity. While the jamming process is well established for fixed geometries, the nature and dynamics of jamming for a diverse class of soft materials and deformable substrates, including emulsions and biological matter, remains unknown. Here we propose a new scenario, metric jamming, where rigidification occurs on a surface that has been deformed from its ground state. Unlike classical jamming processes that exhibit discrete mechanical transitions, surprisingly we find that metric jammed states possess mechanical properties continuously tunable between those of classically jammed and conventional elastic media. The compact and curved geometry significantly alters the vibrational spectra of the structures relative to jamming in flat Euclidean space, and metric jammed systems also possess new types of vibrational mode that couple particle and shape degrees of freedom. Our work provides a theoretical framework that unifies our understanding of solidification processes that take place on deformable media and lays the groundwork to exploit jamming for the control and stabilization of shape in self-assembly processes.
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Affiliation(s)
- Zhaoyu Xie
- Department of Physics & Astronomy, Tufts University, 574 Boston Ave, Medford, MA 02155, USA.
| | - Timothy J Atherton
- Department of Physics & Astronomy, Tufts University, 574 Boston Ave, Medford, MA 02155, USA.
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3
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Caprini L, Marini Bettolo Marconi U, Löwen H. Entropy production and collective excitations of crystals out of equilibrium: The concept of entropons. Phys Rev E 2023; 108:044603. [PMID: 37978682 DOI: 10.1103/physreve.108.044603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 09/21/2023] [Indexed: 11/19/2023]
Abstract
We study the collective vibrational excitations of crystals under out-of-equilibrium steady conditions that give rise to entropy production. Their excitation spectrum comprises equilibriumlike phonons of thermal origin and additional collective excitations called entropons because each of them represents a mode of spectral entropy production. Entropons coexist with phonons and dominate them when the system is far from equilibrium while they are negligible in near-equilibrium regimes. The concept of entropons has been recently introduced and verified in a special case of crystals formed by self-propelled particles. Here we show that entropons exist in a broader class of active crystals that are intrinsically out of equilibrium and characterized by the lack of detailed balance. After a general derivation, several explicit examples are discussed, including crystals consisting of particles with alignment interactions and frictional contact forces.
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Affiliation(s)
- L Caprini
- Heinrich-Heine-Universität Düsseldorf, Institut für Theoretische Physik II: Weiche Materie, Universitätsstrasse, 40225 Düsseldorf, Germany
| | - U Marini Bettolo Marconi
- Physics Department, Scuola di Scienze e Tecnologie, Università di Camerino - via Madonna delle Carceri, 62032 Camerino, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, Via A. Pascoli, 06123 Perugia, Italy
| | - H Löwen
- Heinrich-Heine-Universität Düsseldorf, Institut für Theoretische Physik II: Weiche Materie, Universitätsstrasse, 40225 Düsseldorf, Germany
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4
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Xia Y, Yang X, Huang J, Liu R, Xu N, Yang M, Chen K. Orientational Order in Dense Colloidal Liquids and Glasses. PHYSICAL REVIEW LETTERS 2023; 131:128201. [PMID: 37802956 DOI: 10.1103/physrevlett.131.128201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/07/2023] [Accepted: 08/30/2023] [Indexed: 10/08/2023]
Abstract
We construct structural order parameters based on local angular and radial distribution functions in dense colloidal suspensions. All the order parameters show significant correlations to local dynamics in the supercooled and glass regime. In particular, the correlations between the orientational order and dynamical heterogeneity are consistently higher than those between the conventional two-body structural entropy and local dynamics. The structure-dynamics correlations can be explained by a excitation model with the energy barrier depending on local structural order. Our results suggest that in dense disordered packings, local orientational order is higher than translational order, and plays a more important role in determining the dynamics in glassy systems.
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Affiliation(s)
- Yiming Xia
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Xiunan Yang
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Junchao Huang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Microscale Magnetic Resonance and Department of Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Rui Liu
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Science, Beijing 100049, People's Republic of China
| | - Ning Xu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Microscale Magnetic Resonance and Department of Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Mingcheng Yang
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Science, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Ke Chen
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Science, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
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5
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Nguyên TTT, Doanh T, Bot AL, Dalmas D. An acoustic signature of extreme failure on model granular materials. Sci Rep 2022; 12:18304. [PMID: 36316344 PMCID: PMC9622919 DOI: 10.1038/s41598-022-20231-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023] Open
Abstract
Unexpectedly, granular materials can fail, the structure even destroyed, spontaneously in simple isotropic compression with stick-slip-like frictional behaviour. This extreme behaviour is conceptually impossible for saturated two-phase assembly in classical granular physics. Furthermore, the triggering mechanisms of these laboratory events remain mysterious, as in natural earthquakes. Here, we report a new interpretation of these failures in under-explored isotropic compression using the time-frequency analysis of Cauchy continuous wavelet transform of acoustic emissions and multiphysics numerical simulations. Wavelet transformation techniques can give insights into the temporal evolution of the state of granular materials en route to failure and offer a plausible explanation of the distinctive hearing sound of the stick-slip phenomenon. We also extend the traditional statistical seismic Gutenberg-Richter power-law behaviour for hypothetical biggest earthquakes based on the mechanisms of stick-slip frictional instability, using very large artificial isotropic labquakes and the ultimate unpredictable liquefaction failure.
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Affiliation(s)
- T T T Nguyên
- Ecole Nationale des Travaux Publics de l'Etat, LTDS (UMR 5513), Vaulx en Velin, France
| | - T Doanh
- Ecole Nationale des Travaux Publics de l'Etat, LTDS (UMR 5513), Vaulx en Velin, France.
| | - A Le Bot
- Ecole Centrale de Lyon, LTDS (UMR 5513), Ecully, France
| | - D Dalmas
- Ecole Centrale de Lyon, LTDS (UMR 5513), Ecully, France
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6
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Giannini JA, Stanifer EM, Manning ML. Searching for structural predictors of plasticity in dense active packings. SOFT MATTER 2022; 18:1540-1553. [PMID: 35107478 DOI: 10.1039/d1sm01675j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In amorphous solids subject to shear or thermal excitation, so-called structural indicators have been developed that predict locations of future plasticity or particle rearrangements. An open question is whether similar tools can be used in dense active materials, but a challenge is that under most circumstances, active systems do not possess well-defined solid reference configurations. We develop a computational model for a dense active crowd attracted to a point of interest, which does permit a mechanically stable reference state in the limit of infinitely persistent motion. Previous work on a similar system suggested that the collective motion of crowds could be predicted by inverting a matrix of time-averaged two-particle correlation functions. Seeking a first-principles understanding of this result, we demonstrate that this active matter system maps directly onto a granular packing in the presence of an external potential, and extend an existing structural indicator based on linear response to predict plasticity in the presence of noisy dynamics. We find that the strong pressure gradient necessitated by the directed activity, as well as a self-generated free boundary, strongly impact the linear response of the system. In low-pressure regions the linear-response-based indicator is predictive, but it does not work well in the high-pressure interior of our active packings. Our findings motivate and inform future work that could better formulate structure-dynamics predictions in systems with strong pressure gradients.
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Affiliation(s)
- Julia A Giannini
- Department of Physics, Syracuse University, Syracuse, New York 13244, USA.
- BioInspired Institute, Syracuse University, Syracuse, New York 13244, USA
| | - Ethan M Stanifer
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - M Lisa Manning
- Department of Physics, Syracuse University, Syracuse, New York 13244, USA.
- BioInspired Institute, Syracuse University, Syracuse, New York 13244, USA
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7
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Ma X, Mishra CK, Habdas P, Yodh AG. Structural and short-time vibrational properties of colloidal glasses and supercooled liquids in the vicinity of the re-entrant glass transition. J Chem Phys 2021; 155:074902. [PMID: 34418931 DOI: 10.1063/5.0059084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We investigate the short-time vibrational properties and structure of two-dimensional, bidisperse, colloidal glasses and supercooled liquids in the vicinity of the re-entrant glass transition, as a function of interparticle depletion attraction strength. The long-time spatiotemporal dynamics of the samples are measured to be non-monotonic, confirming that the suspensions evolve from repulsive glass to supercooled liquid to attractive glass with increasing depletion attraction. Here, we search for vibrational signatures of the re-entrant behavior in the short-time spatiotemporal dynamics, i.e., dynamics associated with particle motion inside its nearest-neighbor cage. Interestingly, we observe that the anharmonicity of these in-cage vibrations varies non-monotonically with increasing attraction strength, consistent with the non-monotonic long-time structural relaxation dynamics of the re-entrant glass. We also extract effective spring constants between neighboring particles; we find that spring stiffness involving small particles also varies non-monotonically with increasing attraction strength, while stiffness between large particles increases monotonically. Last, from study of depletion-dependent local structure and vibration participation fractions, we gain microscopic insight into the particle-size-dependent contributions to short-time vibrational modes in the glass and supercooled liquid states.
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Affiliation(s)
- Xiaoguang Ma
- Center for Complex Flows and Soft Matter Research, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Chandan K Mishra
- Discipline of Physics, Indian Institute of Technology (IIT) Gandhinagar Palaj, Gandhinagar, Gujarat 382355, India
| | - P Habdas
- Department of Physics, Saint Joseph's University, Philadelphia, Pennsylvania 19131, USA
| | - A G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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8
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Chen Y, Tan X, Wang H, Zhang Z, Kosterlitz JM, Ling XS. 2D Colloidal Crystals with Anisotropic Impurities. PHYSICAL REVIEW LETTERS 2021; 127:018004. [PMID: 34270301 DOI: 10.1103/physrevlett.127.018004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/13/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
We report a study of 2D colloidal crystals with anisotropic ellipsoid impurities using video microscopy. It is found that at low impurity densities, the impurity particles behave like floating disorder with which the quasi-long-range orientational order survives and the elasticity of the system is actually enhanced. There is a critical impurity density above which the 2D crystal loses the quasi-long-range orientational order. At high impurity densities, the 2D crystal breaks into polycrystalline domains separated by grain boundaries where the impurity particles aggregate. This transition is accompanied by a decrease in the elastic moduli, and it is associated with strong heterogeneous dynamics in the system. The correlation length vs impurity density in the disordered phase exhibits an essential singularity at the critical impurity density.
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Affiliation(s)
- Ya Chen
- Institute for Advanced Study, Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
| | - Xinlan Tan
- Institute for Advanced Study, Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
| | - Huaguang Wang
- Institute for Advanced Study, Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - Zexin Zhang
- Institute for Advanced Study, Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - J M Kosterlitz
- Department of Physics, Brown University, Providence, Rhode Island 02912, USA
| | - Xinsheng Sean Ling
- Department of Physics, Brown University, Providence, Rhode Island 02912, USA
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9
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Donofrio CJ, Weeks ER. Neglecting polydispersity degrades propensity measurements in supercooled liquids. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2021; 44:65. [PMID: 33970360 DOI: 10.1140/epje/s10189-021-00049-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/03/2021] [Indexed: 06/12/2023]
Abstract
We conduct molecular dynamics simulations of a bidisperse Kob-Andersen (KA) glass former, modified to add in additional polydispersity. The original KA system is known to exhibit dynamical heterogeneity. Prior work defined propensity, the mean motion of a particle averaged over simulations reconstructing the initial positions of all particles but with randomized velocities. The existence of propensity shows that structure and dynamics are connected. In this paper, we study systems which mimic problems that would be encountered in measuring propensity in a colloidal glass former, where particles are polydisperse (they have slight size variations). We mimic polydispersity by altering the bidisperse KA system into a quartet consisting of particles both slightly larger and slightly smaller than the parent particles in the original bidisperse system. We then introduce errors into the reconstruction of the initial positions that mimic mistakes one might make in a colloidal experiment. The mistakes degrade the propensity measurement, in some cases nearly completely; one no longer has an iso-configurational ensemble in any useful sense. Our results show that a polydisperse sample is suitable for propensity measurements provided one avoids reconstruction mistakes.
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Affiliation(s)
| | - Eric R Weeks
- Department of Physics, Emory University, Atlanta, GA, 30322, USA.
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10
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Deng L, Zhao C, Xu Z, Zheng W. Critical point of jamming transition in two-dimensional monodisperse systems. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2020; 43:75. [PMID: 33306156 DOI: 10.1140/epje/i2020-11998-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 11/02/2020] [Indexed: 06/12/2023]
Abstract
The existence of amorphous packings in two-dimensional monodisperse system is a classical unsolved problem. We get the energy minimum state by the energy minimization method of enthalpy under constant pressure conditions. Firstly, we find that there are two peaks in the experiment, which demonstrate the interesting features of the coexistence of crystals and amorphous crystals. And then, we confirm the critical point of jamming transition of the two-dimensional monodisperse is [Formula: see text]. Finally, we prove that the jamming scaling is still satisfied in two-dimensional monodispersed system: [Formula: see text] and vanishes as [Formula: see text], and the boson peak shifts to lower frequencies for less compressed systems.
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Affiliation(s)
- Liping Deng
- Institute of Public Safety and Big Data, College of Data Science, Taiyuan University of Technology, 030060, Taiyuan, China
- Key Laboratory of Impact and Safety Engineering, Ministry of Education, Ningbo University, 315211, Ningbo, China
| | - Cai Zhao
- Institute of Public Safety and Big Data, College of Data Science, Taiyuan University of Technology, 030060, Taiyuan, China
| | - Zhenhuan Xu
- Institute of Public Safety and Big Data, College of Data Science, Taiyuan University of Technology, 030060, Taiyuan, China
| | - Wen Zheng
- Institute of Public Safety and Big Data, College of Data Science, Taiyuan University of Technology, 030060, Taiyuan, China.
- Key Laboratory of Impact and Safety Engineering, Ministry of Education, Ningbo University, 315211, Ningbo, China.
- Center for Healthy Big Data, Changzhi Medical College, 046000, Changzhi, Shanxi, China.
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11
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Arceri F, Corwin EI. Vibrational Properties of Hard and Soft Spheres Are Unified at Jamming. PHYSICAL REVIEW LETTERS 2020; 124:238002. [PMID: 32603144 DOI: 10.1103/physrevlett.124.238002] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
The unconventional thermal properties of jammed amorphous solids are directly related to their density of vibrational states. While the vibrational spectrum of jammed soft sphere solids has been fully described, the vibrational spectrum of hard spheres, a model glass former often related to physical colloidal glasses, is still unknown due to the difficulty of treating the nonanalytic interaction potential. We bypass this difficulty using the recently described effective interaction potential for the free energy of thermal hard spheres. By minimizing this effective free energy, we mimic the rapid compression of hard spheres and produce typical configurations of the thermal system. We measure the resulting vibrational spectrum and characterize its evolution toward the jamming point where configurations of hard and soft spheres are trivially unified. For densities approaching jamming from below, we observe low-frequency modes which agree with those found in numerical simulations of jammed soft spheres. Our measurements of the vibrational structure demonstrate that the jamming universality extends away from jamming: hard sphere thermal systems below jamming exhibit the same vibrational spectra as thermal and athermal soft sphere systems above the transition.
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Affiliation(s)
- Francesco Arceri
- Department of Physics, University of Oregon, Eugene, Oregon 97403, USA
| | - Eric I Corwin
- Department of Physics, University of Oregon, Eugene, Oregon 97403, USA
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12
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Li XY, Zhang HP, Lan S, Abernathy DL, Otomo T, Wang FW, Ren Y, Li MZ, Wang XL. Observation of High-Frequency Transverse Phonons in Metallic Glasses. PHYSICAL REVIEW LETTERS 2020; 124:225902. [PMID: 32567931 DOI: 10.1103/physrevlett.124.225902] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
Using inelastic neutron scattering and molecular dynamics simulations on a model Zr-Cu-Al metallic glass, we show that transverse phonons persist well into the high-frequency regime, and can be detected at large momentum transfer. Furthermore, the apparent peak width of the transverse phonons was found to follow the static structure factor. The one-to-one correspondence, which was demonstrated for both Zr-Cu-Al metallic glass and a three-dimensional Lennard-Jones model glass, suggests a universal correlation between the phonon dynamics and the underlying disordered structure. This remarkable correlation, not found for longitudinal phonons, underscores the key role that transverse phonons hold for understanding the structure-dynamics relationship in disordered materials.
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Affiliation(s)
- X Y Li
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - H P Zhang
- Department of Physics, Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
| | - S Lan
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China
- Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Avenue, Nanjing 210094, China
| | - D L Abernathy
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - T Otomo
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801, Japan
| | - F W Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - Y Ren
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - M Z Li
- Department of Physics, Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
| | - X-L Wang
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China
- Center for Neutron Scattering, City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Shenzhen 518057, China
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13
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Henkes S, Kostanjevec K, Collinson JM, Sknepnek R, Bertin E. Dense active matter model of motion patterns in confluent cell monolayers. Nat Commun 2020; 11:1405. [PMID: 32179745 PMCID: PMC7075903 DOI: 10.1038/s41467-020-15164-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 02/07/2020] [Indexed: 11/09/2022] Open
Abstract
Epithelial cell monolayers show remarkable displacement and velocity correlations over distances of ten or more cell sizes that are reminiscent of supercooled liquids and active nematics. We show that many observed features can be described within the framework of dense active matter, and argue that persistent uncoordinated cell motility coupled to the collective elastic modes of the cell sheet is sufficient to produce swirl-like correlations. We obtain this result using both continuum active linear elasticity and a normal modes formalism, and validate analytical predictions with numerical simulations of two agent-based cell models, soft elastic particles and the self-propelled Voronoi model together with in-vitro experiments of confluent corneal epithelial cell sheets. Simulations and normal mode analysis perfectly match when tissue-level reorganisation occurs on times longer than the persistence time of cell motility. Our analytical model quantitatively matches measured velocity correlation functions over more than a decade with a single fitting parameter.
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Affiliation(s)
- Silke Henkes
- School of Mathematics, University of Bristol, Bristol, BS8 1TW, United Kingdom.
- Institute of Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, AB24 3UE, United Kingdom.
| | - Kaja Kostanjevec
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
| | - J Martin Collinson
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, AB25 2ZD, United Kingdom
| | - Rastko Sknepnek
- School of Science and Engineering, University of Dundee, Dundee, DD1 4HN, United Kingdom.
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom.
| | - Eric Bertin
- Université Grenoble Alpes and CNRS, LIPHY, F-38000, Grenoble, France.
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14
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Cho HW, Mugnai ML, Kirkpatrick TR, Thirumalai D. Fragile-to-strong crossover, growing length scales, and dynamic heterogeneity in Wigner glasses. Phys Rev E 2020; 101:032605. [PMID: 32290023 DOI: 10.1103/physreve.101.032605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/26/2020] [Indexed: 06/11/2023]
Abstract
Colloidal particles, which are ubiquitous, have become ideal testing grounds for the structural glass transition theories. In these systems glassy behavior arises as the density of the particles is increased. Thus, soft colloidal particles with varying degree of softness capture diverse glass-forming properties, observed normally in molecular glasses. Brownian dynamics simulations for a binary mixture of micron-sized charged colloidal suspensions show that tuning the softness of the interaction potential, achievable by changing the monovalent salt concentration results in a continuous transition from fragile to strong behavior. Remarkably, this is found in a system where the well characterized interaction potential between the colloidal particles is isotropic. We also show that the predictions of the random first-order transition (RFOT) theory quantitatively describes the universal features such as the growing correlation length, ξ∼(ϕ_{K}/ϕ-1)^{-ν} with ν=2/3 where ϕ_{K}, the analog of the Kauzmann temperature, depends on the salt concentration. As anticipated by the RFOT predictions, we establish a causal relationship between the growing correlation length and a steep increase in the relaxation time and dynamic heterogeneity as the system is compressed. The broad range of fragility observed in Wigner glasses is used to draw analogies with molecular and polymer glasses. The large variations in the fragility are normally found only when the temperature dependence of the viscosity is examined for a large class of diverse glass-forming materials. In sharp contrast, this is vividly illustrated in a single system that can be experimentally probed. Our work also shows that the RFOT predictions are accurate in describing the dynamics over the entire density range, regardless of the fragility of the glasses.
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Affiliation(s)
- Hyun Woo Cho
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA
| | - Mauro L Mugnai
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA
| | - T R Kirkpatrick
- Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - D Thirumalai
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA
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15
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Landes FP, Biroli G, Dauchot O, Liu AJ, Reichman DR. Attractive versus truncated repulsive supercooled liquids: The dynamics is encoded in the pair correlation function. Phys Rev E 2020; 101:010602. [PMID: 32069631 DOI: 10.1103/physreve.101.010602] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Indexed: 11/07/2022]
Abstract
We 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 despite having nearly identical pair correlation functions. We demonstrate that a properly weighted integral of the pair correlation function, which amplifies the subtle differences between the two systems, correctly captures their dynamical differences. The weights are obtained from a standard machine learning algorithm.
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Affiliation(s)
- François P Landes
- Université Paris-Saclay, CNRS, Inria, Laboratoire de recherche en informatique, TAU team, 91405 Orsay, France.,Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, 75005 Paris, France.,Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
| | - Giulio Biroli
- Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, 75005 Paris, France
| | - Olivier Dauchot
- UMR Gulliver 7083 CNRS, ESPCI ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
| | - Andrea J Liu
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - David R Reichman
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
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16
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Boromand A, Signoriello A, Lowensohn J, Orellana CS, Weeks ER, Ye F, Shattuck MD, O'Hern CS. The role of deformability in determining the structural and mechanical properties of bubbles and emulsions. SOFT MATTER 2019; 15:5854-5865. [PMID: 31246221 DOI: 10.1039/c9sm00775j] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We perform computational studies of jammed particle packings in two dimensions undergoing isotropic compression using the well-characterized soft particle (SP) model and deformable particle (DP) model that we developed for bubbles and emulsions. In the SP model, circular particles are allowed to overlap, generating purely repulsive forces. In the DP model, particles minimize their perimeter, while deforming at fixed area to avoid overlap during compression. We compare the structural and mechanical properties of jammed packings generated using the SP and DP models as a function of the packing fraction ρ, instead of the reduced number density φ. We show that near jamming onset the excess contact number Δz = z - zJ and shear modulus G scale as Δρ0.5 in the large system limit for both models, where Δρ = ρ - ρJ and zJ ≈ 4 and ρJ ≈ 0.842 are the values at jamming onset. Δz and G for the SP and DP models begin to differ for ρ ⪆ 0.88. In this regime, Δz ∼ G can be described by a sum of two power-laws in Δρ, i.e. Δz ∼ G ∼ C0Δρ0.5 + C1Δρ1.0 to lowest order. We show that the ratio C1/C0 is much larger for the DP model compared to that for the SP model. We also characterize the void space in jammed packings as a function of ρ. We find that the DP model can describe the formation of Plateau borders as ρ → 1. We further show that the results for z and the shape factor A versus ρ for the DP model agree with recent experimental studies of foams and emulsions.
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Affiliation(s)
- Arman Boromand
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA. and Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Alexandra Signoriello
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA
| | - Janna Lowensohn
- Department of Physics, Emory University, Atlanta, Georgia 30322, USA
| | - Carlos S Orellana
- Department of Physics, Emory University, Atlanta, Georgia 30322, USA
| | - Eric R Weeks
- Department of Physics, Emory University, Atlanta, Georgia 30322, USA
| | - Fangfu Ye
- Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China and School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Mark D Shattuck
- Benjamin Levich Institute and Physics Department, The City College of New York, New York, New York 10031, USA
| | - Corey S O'Hern
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, USA. and Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut 06520, USA and Department of Physics, Yale University, New Haven, Connecticut 06520, USA and Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA.
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17
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Yang X, Tong H, Wang WH, Chen K. Emergence and percolation of rigid domains during the colloidal glass transition. Phys Rev E 2019; 99:062610. [PMID: 31330594 DOI: 10.1103/physreve.99.062610] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Indexed: 06/10/2023]
Abstract
Using video microscopy, we measure local spatial constraints in disordered binary colloidal samples, ranging from dilute fluids to jammed glasses, and probe their spatial and temporal correlations to local dynamics during the glass transition. We observe the emergence of significant correlations between constraints and local dynamics within the Lindemann criterion, which coincides with the onset of glassy dynamics in supercooled liquids. Rigid domains in fluids are identified based on local constraints and demonstrate a percolation transition near the glass transition, accompanied by the emergence of dynamical heterogeneities. Our results show that spatial constraint instead of the geometry of amorphous structures is the key that connects the complex spatial-temporal correlations in disordered materials.
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Affiliation(s)
- Xiunan Yang
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Hua Tong
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Wei-Hua Wang
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Ke Chen
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
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18
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Ikeda H. Universal non-mean-field scaling in the density of states of amorphous solids. Phys Rev E 2019; 99:050901. [PMID: 31212547 DOI: 10.1103/physreve.99.050901] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Indexed: 11/07/2022]
Abstract
Amorphous solids have excess soft modes in addition to the phonon modes described by the Debye theory. Recent numerical results show that if the phonon modes are carefully removed, the density of state of the excess soft modes exhibit universal quartic scaling, independent of the interaction potential, preparation protocol, and spatial dimensions. We hereby provide a theoretical framework to describe this universal scaling behavior. For this purpose, we extend the mean-field theory to include the effects of finite-dimensional fluctuation. Based on a semiphenomenological argument, we show that mean-field quadratic scaling is replaced by the quartic scaling in finite dimensions. Furthermore, we apply our formalism to explain the pressure and protocol dependence of the excess soft modes.
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Affiliation(s)
- Harukuni Ikeda
- École Normale Supérieure, UMR 8549 CNRS, 24 Rue Lhomond, 75005 Paris, France
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19
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A universal state and its relaxation mechanisms of long-range interacting polygons. Nat Commun 2019; 10:1737. [PMID: 30988297 PMCID: PMC6465257 DOI: 10.1038/s41467-019-09795-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 03/31/2019] [Indexed: 11/08/2022] Open
Abstract
Using polygonal magnetic particles, we conduct experiments to explore the space-filling properties of anisotropic blocks with long-range interactions. In contrast to previous studies, we obtain the surprising finding that our systems' structures do not depend on the shape of building blocks: a single state, the hexagonal plastic crystal, appears as a universal attractor for a wide range of different polygons. This robust particle-shape independency appears as the interactions go beyond nearest neighbors. Particle shape plays an essential role in system relaxation, and determines the basic relaxation dynamics through a microscopic control parameter, internal roughness, produced by particle vertices. Thus our study reveals a new pattern-forming paradigm, in which particle shape plays little role in the static structure but determines the essential relaxation dynamics. Due to the ubiquity of long-range interactions and anisotropic building blocks, our discovery may shed new light on diverse problems involving structure formation, self-assembly, and packing.
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20
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Zong Y, Chen K, Mason TG, Zhao K. Vibrational Modes and Dynamic Heterogeneity in a Near-Equilibrium 2D Glass of Colloidal Kites. PHYSICAL REVIEW LETTERS 2018; 121:228003. [PMID: 30547612 DOI: 10.1103/physrevlett.121.228003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/04/2018] [Indexed: 06/09/2023]
Abstract
Using video microscopy and particle-tracking techniques developed for dense Brownian systems of polygons, we study the structure-dynamics relationship in a near-equilibrium 2D glass consisting of anisotropic Penrose kite-shaped colloids. Detailed vibrational properties of kite glasses, both translational and rotational, are obtained using covariance matrix techniques. Different from other colloidal glasses of spheres and ellipsoids, the vibrational modes of kite glasses at low frequencies show a strong translational character with spatially localized rotational modes and extended translational modes. Low-frequency quasilocalized soft modes commonly found in sphere glasses are absent in the translational phonon modes of kite glasses. Soft modes are observed predominantly in the rotational vibrations and correlate well with the spatial distribution of Debye-Waller factors. The local structural entropy field shows a strong correlation with the observed dynamic heterogeneity.
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Affiliation(s)
- Yiwu Zong
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | - Ke Chen
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Thomas G Mason
- Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, California 90095, USA
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California 90095, USA
| | - Kun Zhao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
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21
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Apparent strength versus universality in glasses of soft compressible colloids. Sci Rep 2018; 8:16817. [PMID: 30429509 PMCID: PMC6235924 DOI: 10.1038/s41598-018-35187-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/26/2018] [Indexed: 11/08/2022] Open
Abstract
Microgel colloids, solvent swollen hydrogel particles of microscopic size, are in osmotic equilibrium with their surroundings. This has a profound effect on the behaviour of dense solutions of these polymeric colloids, most notably their ability to swell and deswell depending on the osmotic pressure of the system as a whole. Here we develop a minimal simulation model to treat this intrinsic volume regulation in order to explore the effects this has on the properties of dense solutions close to a liquid-solid transition. We demonstrate how the softness dependent volume regulation of particles gives rise to an apparent change in the fragility of the colloidal glass transition, which can be scaled out through the use of an adjusted volume fraction that accounts for changes in particle size. Moreover, we show how the same model can be used to explain the selective deswelling of soft microgels in a crystalline matrix of harder particles leading to robust crystals free of defects. Our results not only highlight the non-trivial effects of osmotic regulation in governing the apparent physics of microgel suspensions, but also provides a platform to efficiently account for particle deswelling in simulations.
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22
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Brito C, Ikeda H, Urbani P, Wyart M, Zamponi F. Universality of jamming of nonspherical particles. Proc Natl Acad Sci U S A 2018; 115:11736-11741. [PMID: 30381457 PMCID: PMC6243269 DOI: 10.1073/pnas.1812457115] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Amorphous packings of nonspherical particles such as ellipsoids and spherocylinders are known to be hypostatic: The number of mechanical contacts between particles is smaller than the number of degrees of freedom, thus violating Maxwell's mechanical stability criterion. In this work, we propose a general theory of hypostatic amorphous packings and the associated jamming transition. First, we show that many systems fall into a same universality class. As an example, we explicitly map ellipsoids into a system of "breathing" particles. We show by using a marginal stability argument that in both cases jammed packings are hypostatic and that the critical exponents related to the contact number and the vibrational density of states are the same. Furthermore, we introduce a generalized perceptron model which can be solved analytically by the replica method. The analytical solution predicts critical exponents in the same hypostatic jamming universality class. Our analysis further reveals that the force and gap distributions of hypostatic jamming do not show power-law behavior, in marked contrast to the isostatic jamming of spherical particles. Finally, we confirm our theoretical predictions by numerical simulations.
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Affiliation(s)
- Carolina Brito
- Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, Brazil
| | - Harukuni Ikeda
- Laboratoire de Physique Theórique, Département de Physique de l'École Normale Supérieure, École Normale Supérieure, Paris Sciences et Lettres University, Sorbonne Université, CNRS, 75005 Paris, France;
| | - Pierfrancesco Urbani
- Institut de Physique Théorique, Université Paris Saclay, CNRS, Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), F-91191 Gif-sur-Yvette, France
| | - Matthieu Wyart
- Institute of Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Francesco Zamponi
- Laboratoire de Physique Theórique, Département de Physique de l'École Normale Supérieure, École Normale Supérieure, Paris Sciences et Lettres University, Sorbonne Université, CNRS, 75005 Paris, France
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23
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Woodhouse FG, Ronellenfitsch H, Dunkel J. Autonomous Actuation of Zero Modes in Mechanical Networks Far from Equilibrium. PHYSICAL REVIEW LETTERS 2018; 121:178001. [PMID: 30411906 DOI: 10.1103/physrevlett.121.178001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/04/2018] [Indexed: 06/08/2023]
Abstract
A zero mode, or floppy mode, is a nontrivial coupling of mechanical components yielding a degree of freedom with no resistance to deformation. Engineered zero modes have the potential to act as microscopic motors or memory devices, but this requires an internal actuation mechanism that can overcome unwanted fluctuations in other modes and the dissipation inherent in real systems. In this Letter, we show theoretically and experimentally that complex zero modes in mechanical networks can be selectively mobilized by nonequilibrium activity. We find that a correlated active bath actuates an infinitesimal zero mode while simultaneously suppressing fluctuations in higher modes compared to thermal fluctuations, which we experimentally mimic by high frequency shaking of a physical network. Furthermore, self-propulsive dynamics spontaneously mobilize finite mechanisms as exemplified by a self-propelled topological soliton. Nonequilibrium activity thus enables autonomous actuation of coordinated mechanisms engineered through network topology.
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Affiliation(s)
- Francis G Woodhouse
- Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom
| | - Henrik Ronellenfitsch
- Department of Mathematics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
| | - Jörn Dunkel
- Department of Mathematics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA
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24
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Wang PY, Mason TG. A Brownian quasi-crystal of pre-assembled colloidal Penrose tiles. Nature 2018; 561:94-99. [PMID: 30158703 DOI: 10.1038/s41586-018-0464-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 07/13/2018] [Indexed: 11/10/2022]
Abstract
Penrose's pentagonal P2 quasi-crystal1-4 is a beautiful, hierarchically organized multiscale structure in which kite- and dart-shaped tiles are arranged into local motifs, such as pentagonal stars, which are in turn arranged into various close-packed superstructural patterns that become increasingly complex at larger length scales. Although certain types of quasi-periodic structure have been observed in hard and soft matter, such structures are difficult to engineer, especially over large areas, because generating the necessary, highly specific interactions between constituent building blocks is challenging. Previously reported soft-matter quasi-crystals of dendrimers5, triblock copolymers6, nanoparticles7 and polymeric micelles8 have been limited to 12- or 18-fold symmetries. Because routes for self-assembling complex colloidal building blocks9-11 into low-defect dynamic superstructures remain limited12, alternative methods, such as using optical and directed assembly, are being explored13,14. Holographic laser tweezers15 and optical standing waves16 have been used to hold microspheres in local quasi-crystalline arrangements, and magnetic microspheres of two different sizes have been assembled into local five-fold-symmetric quasi-crystalline arrangements in two dimensions17. But a Penrose quasi-crystal of mobile colloidal tiles has hitherto not been fabricated over large areas. Here we report such a quasi-crystal in two dimensions, created using a highly parallelizable method of lithographic printing and subsequent release of pre-assembled kite- and dart-shaped tiles into a solution-dispersion containing a depletion agent. After release, the positions and orientations of the tiles within the quasi-crystal can fluctuate, and these tiles undergo random, Brownian motion in the monolayer owing to frequent collisions between neighbouring tiles, even after the system reaches equilibrium. Using optical microscopy, we study both the equilibrium fluctuations of the system at high tile densities and also the 'melting' of the pattern as the tile density is lowered. At high tile densities we find signatures of a five-fold pentatic liquid quasi-crystalline phase, analogous to a six-fold hexatic liquid crystal. Our fabrication approach is applicable to tiles of different sizes and shapes, and with different initial positions and orientations, enabling the creation of two-dimensional quasi-crystalline systems (and other systems that possess multiscale complexity at high tile densities) beyond those of current self- or directed-assembly methods18-20. We anticipate that our approach for generating lithographically pre-assembled monolayers could be extended to create three-dimensional Brownian systems of fluctuating particles with custom-designed shapes through holographic lithography21,22 or stereolithography23.
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Affiliation(s)
- Po-Yuan Wang
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, USA.,Department of Materials Science and Engineering, University of California-Los Angeles, Los Angeles, CA, USA
| | - Thomas G Mason
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA, USA. .,Department of Physics and Astronomy, University of California-Los Angeles, Los Angeles, CA, USA.
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25
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Philippe AM, Truzzolillo D, Galvan-Myoshi J, Dieudonné-George P, Trappe V, Berthier L, Cipelletti L. Glass transition of soft colloids. Phys Rev E 2018; 97:040601. [PMID: 29758608 DOI: 10.1103/physreve.97.040601] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Indexed: 11/07/2022]
Abstract
We explore the glassy dynamics of soft colloids using microgels and charged particles interacting by steric and screened Coulomb interactions, respectively. In the supercooled regime, the structural relaxation time τ_{α} of both systems grows steeply with volume fraction, reminiscent of the behavior of colloidal hard spheres. Computer simulations confirm that the growth of τ_{α} on approaching the glass transition is independent of particle softness. By contrast, softness becomes relevant at very large packing fractions when the system falls out of equilibrium. In this nonequilibrium regime, τ_{α} depends surprisingly weakly on packing fraction, and time correlation functions exhibit a compressed exponential decay consistent with stress-driven relaxation. The transition to this novel regime coincides with the onset of an anomalous decrease in local order with increasing density typical of ultrasoft systems. We propose that these peculiar dynamics results from the combination of the nonequilibrium aging dynamics expected in the glassy state and the tendency of colloids interacting through soft potentials to refluidize at high packing fractions.
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Affiliation(s)
- Adrian-Marie Philippe
- Laboratoire Charles Coulomb (L2C), University of Montpellier, CNRS, Montpellier, France
| | - Domenico Truzzolillo
- Laboratoire Charles Coulomb (L2C), University of Montpellier, CNRS, Montpellier, France
| | | | | | - Véronique Trappe
- Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Ludovic Berthier
- Laboratoire Charles Coulomb (L2C), University of Montpellier, CNRS, Montpellier, France
| | - Luca Cipelletti
- Laboratoire Charles Coulomb (L2C), University of Montpellier, CNRS, Montpellier, France
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26
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Brzinski TA, Daniels KE. Sounds of Failure: Passive Acoustic Measurements of Excited Vibrational Modes. PHYSICAL REVIEW LETTERS 2018; 120:218003. [PMID: 29883186 DOI: 10.1103/physrevlett.120.218003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 03/13/2018] [Indexed: 06/08/2023]
Abstract
Granular materials can fail through spontaneous events like earthquakes or brittle fracture. However, measurements and analytic models which forecast failure in this class of materials, while of both fundamental and practical interest, remain elusive. Materials including numerical packings of spheres, colloidal glasses, and granular materials have been known to develop an excess of low-frequency vibrational modes as the confining pressure is reduced. Here, we report experiments on sheared granular materials in which we monitor the evolving density of excited modes via passive monitoring of acoustic emissions. We observe a broadening of the distribution of excited modes coincident with both bulk and local plasticity, and evolution in the shape of the distribution before and after bulk failure. These results provide a new interpretation of the changing state of the material on its approach to stick-slip failure.
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Affiliation(s)
- Theodore A Brzinski
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Karen E Daniels
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
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27
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Achilleos V, Theocharis G, Skokos C. Chaos and Anderson-like localization in polydisperse granular chains. Phys Rev E 2018; 97:042220. [PMID: 29758770 DOI: 10.1103/physreve.97.042220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Indexed: 06/08/2023]
Abstract
We investigate the dynamics of highly polydisperse finite granular chains. From the spatiospectral properties of small vibrations, we identify which particular single-particle displacements lead to energy localization. Then, we address a fundamental question: Do granular nonlinearities and the resulting chaotic dynamics destroy this energy localization? Our numerical simulations show that for moderate nonlinearities, the overall system behaves chaotically, and spreading of energy occurs. However, long-lasting chaotic energy localization is observed for particular single-particle excitations in the presence of the nonsmooth nonlinearities. On the other hand, for sufficiently strong nonlinearities, the granular chain reaches energy equipartition. In this case, an equilibrium chaotic state is reached independent of the initial position excitation.
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Affiliation(s)
- V Achilleos
- Laboratoire d'Acoustique de l'Université du Maine, UMR CNRS 6613 Av. O. Messiaen, F-72085 LE MANS Cedex 9, France
| | - G Theocharis
- Laboratoire d'Acoustique de l'Université du Maine, UMR CNRS 6613 Av. O. Messiaen, F-72085 LE MANS Cedex 9, France
| | - Ch Skokos
- Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, South Africa
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28
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Shiba H, Keim P, Kawasaki T. Isolating long-wavelength fluctuation from structural relaxation in two-dimensional glass: cage-relative displacement. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:094004. [PMID: 29345245 DOI: 10.1088/1361-648x/aaa8b8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
It has recently been revealed that long-wavelength fluctuation exists in two-dimensional (2D) glassy systems, having the same origin as that given by the Mermin-Wagner theorem for 2D crystalline solids. In this paper, we discuss how to characterise quantitatively the long-wavelength fluctuation in a molecular dynamics simulation of a lightly supercooled liquid. We employ the cage-relative mean-square displacement (MSD), defined on relative displacement to its cage, to quantitatively separate the long-wavelength fluctuation from the original MSD. For increasing system size the amplitude of acoustic long wavelength fluctuations not only increases but shifts to later times causing a crossover with structural relaxation of caging particles. We further analyse the dynamic correlation length using the cage-relative quantities. It grows as the structural relaxation becomes slower with decreasing temperature, uncovering an overestimation by the four-point correlation function due to the long-wavelength fluctuation. These findings motivate the usage of cage-relative MSD as a starting point for analysis of 2D glassy dynamics.
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Affiliation(s)
- Hayato Shiba
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
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29
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Leahy BD, Lin NY, Cohen I. Quantitative light microscopy of dense suspensions: Colloid science at the next decimal place. Curr Opin Colloid Interface Sci 2018. [DOI: 10.1016/j.cocis.2018.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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30
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Abstract
The normal modes and relaxation rates of weak colloidal gels are investigated in calculations using different models of the hydrodynamic interactions between suspended particles. The relaxation spectrum is computed for freely draining, Rotne-Prager-Yamakawa, and accelerated Stokesian dynamics approximations of the hydrodynamic mobility in a normal mode analysis of a harmonic network representing several colloidal gels. We find that the density of states and spatial structure of the normal modes are fundamentally altered by long-ranged hydrodynamic coupling among the particles. Short-ranged coupling due to hydrodynamic lubrication affects only the relaxation rates of short-wavelength modes. Hydrodynamic models accounting for long-ranged coupling exhibit a microscopic relaxation rate for each normal mode, λ that scales as l^{-2}, where l is the spatial correlation length of the normal mode. For the freely draining approximation, which neglects long-ranged coupling, the microscopic relaxation rate scales as l^{-γ}, where γ varies between three and two with increasing particle volume fraction. A simple phenomenological model of the internal elastic response to normal mode fluctuations is developed, which shows that long-ranged hydrodynamic interactions play a central role in the viscoelasticity of the gel network. Dynamic simulations of hard spheres that gel in response to short-ranged depletion attractions are used to test the applicability of the density of states predictions. For particle concentrations up to 30% by volume, the power law decay of the relaxation modulus in simulations accounting for long-ranged hydrodynamic interactions agrees with predictions generated by the density of states of the corresponding harmonic networks as well as experimental measurements. For higher volume fractions, excluded volume interactions dominate the stress response, and the prediction from the harmonic network density of states fails. Analogous to the Zimm model in polymer physics, our results indicate that long-ranged hydrodynamic interactions play a crucial role in determining the microscopic dynamics and macroscopic properties of weak colloidal gels.
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Affiliation(s)
- Zsigmond Varga
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - James W Swan
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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31
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Hu H, Ruiz PS, Ni R. Entropy Stabilizes Floppy Crystals of Mobile DNA-Coated Colloids. PHYSICAL REVIEW LETTERS 2018; 120:048003. [PMID: 29437422 DOI: 10.1103/physrevlett.120.048003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Indexed: 06/08/2023]
Abstract
Grafting linkers with open ends of complementary single-stranded DNA makes a flexible tool to tune interactions between colloids, which facilitates the design of complex self-assembly structures. Recently, it has been proposed to coat colloids with mobile DNA linkers, which alleviates kinetic barriers without high-density grafting, and also allows the design of valency without patches. However, the self-assembly mechanism of this novel system is poorly understood. Using a combination of theory and simulation, we obtain phase diagrams for the system in both two and three dimensional spaces, and find stable floppy square and CsCl crystals when the binding strength is strong, even in the infinite binding strength limit. We demonstrate that these floppy phases are stabilized by vibrational entropy, and "floppy" modes play an important role in stabilizing the floppy phases for the infinite binding strength limit. This special entropic effect in the self-assembly of mobile DNA-coated colloids is very different from conventional molecular self-assembly, and it offers a new axis to help design novel functional materials using mobile DNA-coated colloids.
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Affiliation(s)
- Hao Hu
- Chemical Engineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore
| | - Pablo Sampedro Ruiz
- Chemical Engineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore
| | - Ran Ni
- Chemical Engineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore
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32
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Lin NYC, Bierbaum M, Cohen I. Determining Quiescent Colloidal Suspension Viscosities Using the Green-Kubo Relation and Image-Based Stress Measurements. PHYSICAL REVIEW LETTERS 2017; 119:138001. [PMID: 29341681 DOI: 10.1103/physrevlett.119.138001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Indexed: 06/07/2023]
Abstract
By combining confocal microscopy and stress assessment from local structural anisotropy, we directly measure stresses in 3D quiescent colloidal liquids. Our noninvasive and nonperturbative method allows us to measure forces ≲50 fN with a small and tunable probing volume, enabling us to resolve the stress fluctuations arising from particle thermal motions. We use the Green-Kubo relation to relate these measured stress fluctuations to the bulk Brownian viscosity at different volume fractions, comparing against simulations and conventional rheometry measurements. We find that the Green-Kubo analysis gives excellent agreement with these prior results, suggesting that similar methods could be applied to investigations of local flow properties in many poorly understood far-from-equilibrium systems, including suspensions that are glassy, strongly sheared, or highly confined.
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Affiliation(s)
- Neil Y C Lin
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Matthew Bierbaum
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
| | - Itai Cohen
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
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33
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Abstract
Glassiness is ubiquitous and diverse in characteristics in nature. Understanding their differences and classification remains a major scientific challenge. Here, we show that scaling of magnetic memories with time can be used to classify magnetic glassy materials into two distinct classes. The systems studied are high temperature superconductor-related materials, spin-orbit Mott insulators, frustrated magnets, and dilute magnetic alloys. Our bulk magnetization measurements reveal that most densely populated magnets exhibit similar memory behavior characterized by a relaxation exponent of \documentclass[12pt]{minimal}
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\begin{document}$$1-n\approx 0.6(1)$$\end{document}1−n≈0.6(1). This exponent is different from \documentclass[12pt]{minimal}
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\begin{document}$$1-{\boldsymbol{n}}\approx 1/3$$\end{document}1−n≈1/3 of dilute magnetic alloys that was ascribed to their hierarchical and fractal energy landscape, and is also different from \documentclass[12pt]{minimal}
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\begin{document}$$1-{\boldsymbol{n}}=1$$\end{document}1−n=1 of the conventional Debye relaxation expected for a spin solid, a state with long range order. Furthermore, our systematic study on dilute magnetic alloys with varying magnetic concentration exhibits crossovers among the two glassy states and spin solid.
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34
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Experimental studies of vibrational modes in a two-dimensional amorphous solid. Nat Commun 2017; 8:67. [PMID: 28694525 PMCID: PMC5503991 DOI: 10.1038/s41467-017-00106-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 05/31/2017] [Indexed: 11/11/2022] Open
Abstract
The boson peak, which represents an excess of vibrational states compared to Debye’s prediction at low frequencies, has been studied extensively, and yet, its nature remains controversial. In this study, we focus on understanding the nature of the boson peak based on the spatial heterogeneity of modulus fluctuations using a simple model system of a highly jammed two-dimensional granular material. Despite the simplicity of our system, we find that the boson peak in our two-dimensional system shows a shape very similar to that of three-dimensional molecular glasses when approaching their boson peak frequencies. Our finding indicates a strong connection between the boson peak and the spatial heterogeneity of shear modulus fluctuations. The low-frequency collective vibrational modes, known as the boson peak, characterize many glasses at low temperature, yet its origin remains elusive. Zhang et al. show a correlation between the boson peak and the spatial heterogeneity of shear modulus fluctuation in a two-dimensional granular system.
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35
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Accelerated crystallization of colloidal glass by mechanical oscillation. Sci Rep 2017; 7:1369. [PMID: 28465535 PMCID: PMC5430959 DOI: 10.1038/s41598-017-01484-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/28/2017] [Indexed: 11/09/2022] Open
Abstract
Crystallization of a hard-sphere colloidal glass by mechanical oscillation is investigated, and accelerated crystallization is found at a specific frequency. The crystallization frequency increases as attractive force between particles increases, indicating that interparticle interaction affects the crystallization frequency. Time scale of the mechanical oscillation is different from that of the slow relaxation, and notable relationship with the low-frequency mode is not observed. The experimental results are not explained by the previously proposed model for crystallization by oscillatory shear. Conversely, we speculate that activations of the fast relaxation and particle motion in crystal-like clusters are possible causes of the observations.
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36
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Huang S, Gawlitza K, von Klitzing R, Steffen W, Auernhammer GK. Structure and Rheology of Microgel Monolayers at the Water/Oil Interface. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02779] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Shilin Huang
- Max Planck Institute
for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Kornelia Gawlitza
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, 10623 Berlin, Germany
| | - Regine von Klitzing
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, 10623 Berlin, Germany
| | - Werner Steffen
- Max Planck Institute
for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
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37
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Buttinoni I, Steinacher M, Spanke HT, Pokki J, Bahmann S, Nelson B, Foffi G, Isa L. Colloidal polycrystalline monolayers under oscillatory shear. Phys Rev E 2017; 95:012610. [PMID: 28208468 DOI: 10.1103/physreve.95.012610] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Indexed: 11/07/2022]
Abstract
In this paper we probe the structural response to oscillatory shear deformations of polycrystalline monolayers of soft repulsive colloids with varying area fraction over a broad range of frequencies and amplitudes. The particles are confined at a fluid interface, sheared using a magnetic microdisk, and imaged through optical microscopy. The structural and mechanical response of soft materials is highly dependent on their microstructure. If crystals are well understood and deform through the creation and mobilization of specific defects, the situation is much more complex for disordered jammed materials, where identifying structural motifs defining plastically rearranging regions remains an elusive task. Our materials fall between these two classes and allow the identification of clear pathways for structural evolution. In particular, we demonstrate that large enough strains are able to fluidize the system, identifying critical strains that fulfill a local Lindemann criterion. Conversely, smaller strains lead to localized and erratic irreversible particle rearrangements due to the motion of structural defects. In this regime, oscillatory shear promotes defect annealing and leads to the growth of large crystalline domains. Numerical simulations help identify the population of rearranging particles with those exhibiting the largest deviatoric stresses and indicate that structural evolution proceeds towards the minimization of the stress stored in the system. The particles showing high deviatoric stresses are localized around grain boundaries and defects, providing a simple criterion to spot regions likely to rearrange plastically under oscillatory shear.
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Affiliation(s)
- Ivo Buttinoni
- Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Mathias Steinacher
- Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Hendrik Th Spanke
- Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Juho Pokki
- Institute of Robotics and Intelligent Systems, ETH Zurich, CH-8092, Zurich, Switzerland
| | - Severin Bahmann
- Institute of Robotics and Intelligent Systems, ETH Zurich, CH-8092, Zurich, Switzerland
| | - Bradley Nelson
- Institute of Robotics and Intelligent Systems, ETH Zurich, CH-8092, Zurich, Switzerland
| | - Giuseppe Foffi
- Laboratoire de Physique des Solides, CNRS, Université Paris-Sud, Université Paris-Saclay, Orsay 91405, France
| | - Lucio Isa
- Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zurich, CH-8093, Zurich, Switzerland
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38
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Tjhung E, Kawasaki T. Excitation of vibrational soft modes in disordered systems using active oscillation. SOFT MATTER 2016; 13:111-118. [PMID: 27221647 DOI: 10.1039/c6sm00788k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We propose a new method to characterize the spatial distribution of particles' vibrations in solids with much lower computational costs compared to the usual normal mode analysis. We excite the specific vibrational mode in a two dimensional athermal jammed system by giving a small amplitude of active oscillation to each particle's size with an identical driving frequency. The response is then obtained as the real time displacements of the particles. We show remarkable correlations between the real time displacements and the eigen vectors obtained from conventional normal mode analysis. More importantly, from these real time displacements, we can measure the participation ratio and spatial polarization of particles' vibrations. From these measurements, we find three distinct frequency regimes which characterize the spatial distribution and correlation of particles' vibrations in jammed amorphous solids. Furthermore, we can possibly apply this method to a much larger system to examine the low frequency behaviour of amorphous solids with a much higher resolution of the frequency space.
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Affiliation(s)
- Elsen Tjhung
- Laboratoire Charles Coulomb, UMR 5221, CNRS and Université Montpellier, Montpellier 34095, France
| | - Takeshi Kawasaki
- Department of Physics, Nagoya University, Nagoya 464-8602, Japan.
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39
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Shiba H, Yamada Y, Kawasaki T, Kim K. Unveiling Dimensionality Dependence of Glassy Dynamics: 2D Infinite Fluctuation Eclipses Inherent Structural Relaxation. PHYSICAL REVIEW LETTERS 2016; 117:245701. [PMID: 28009193 DOI: 10.1103/physrevlett.117.245701] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Indexed: 06/06/2023]
Abstract
By using large-scale molecular dynamics simulations, the dynamics of two-dimensional (2D) supercooled liquids turns out to be dependent on the system size, while the size dependence is not pronounced in three-dimensional (3D) systems. It is demonstrated that the strong system-size effect in 2D amorphous systems originates from the enhanced fluctuations at long wavelengths which are similar to those of 2D crystal phonons. This observation is further supported by the frequency dependence of the vibrational density of states, consisting of the Debye approximation in the low-wave-number limit. However, the system-size effect in the intermediate scattering function becomes negligible when the length scale is larger than the vibrational amplitude. This suggests that the finite-size effect in a 2D system is transient and also that the structural relaxation itself is not fundamentally different from that in a 3D system. In fact, the dynamic correlation lengths estimated from the bond-breakage function, which do not suffer from those enhanced fluctuations, are not size dependent in either 2D or 3D systems.
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Affiliation(s)
- Hayato Shiba
- Institute for Solid State Physics, University of Tokyo, Chiba 277-8581, Japan
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Yasunori Yamada
- Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Takeshi Kawasaki
- Department of Physics, Nagoya University, Nagoya 464-8602, Japan
| | - Kang Kim
- Department of Physics, Niigata University, Niigata 950-2181, Japan
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Osaka 560-8531, Japan
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40
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Seguin A, Dauchot O. Experimental Evidence of the Gardner Phase in a Granular Glass. PHYSICAL REVIEW LETTERS 2016; 117:228001. [PMID: 27925738 DOI: 10.1103/physrevlett.117.228001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Indexed: 06/06/2023]
Abstract
Analyzing the dynamics of a vibrated bidimensional packing of bidisperse granular disks below jamming, we provide evidence of a Gardner phase deep into the glass phase. To do so, we perform several compression cycles within a given realization of the same glass and show that the particles select different average vibrational positions at each cycle, while the neighborhood structure remains unchanged. The separation between the cages obtained for different compression cycles plateaus with an increasing packing fraction, while the mean square displacement steadily decreases. This phenomenology is strikingly similar to that reported in recent numerical observations when entering the Gardner phase, for a mean-field model of glass as well as for hard spheres in finite dimension. We also characterize the distribution of the cage order parameters. Here we note several differences from the numerical results, which could be attributed to activated processes and cage heterogeneities.
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Affiliation(s)
- A Seguin
- Laboratoire FAST, Université Paris-Sud, CNRS, Université Paris-Saclay, F-91405, Orsay, France
- SPEC, CEA, CNRS, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France
| | - O Dauchot
- EC2M, UMR Gulliver 7083 CNRS, ESPCI ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
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41
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Lin J, Jorjadze I, Pontani LL, Wyart M, Brujic J. Evidence for Marginal Stability in Emulsions. PHYSICAL REVIEW LETTERS 2016; 117:208001. [PMID: 27886471 DOI: 10.1103/physrevlett.117.208001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Indexed: 06/06/2023]
Abstract
We report the first measurements of the effect of pressure on vibrational modes in emulsions, which serve as a model for soft frictionless spheres at zero temperature. As a function of the applied pressure, we find that the density of states D(ω) exhibits a low-frequency cutoff ω^{*}, which scales linearly with the number of extra contacts per particle δz. Moreover, for ω<ω^{*}, our results are consistent with D(ω)∼ω^{2}/ω^{*2}, a quadratic behavior whose prefactor is larger than what is expected from Debye theory. This surprising result agrees with recent theoretical findings [E. DeGiuli, A. Laversanne-Finot, G. A. Düring, E. Lerner, and M. Wyart, Soft Matter 10, 5628 (2014); S. Franz, G. Parisi, P. Urbani, and F. Zamponi, Proc. Natl. Acad. Sci. U.S.A. 112, 14539 (2015)]. Finally, the degree of localization of the softest low frequency modes increases with compression, as shown by the participation ratio as well as their spatial configurations. Overall, our observations show that emulsions are marginally stable and display non-plane-wave modes up to vanishing frequencies.
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Affiliation(s)
- Jie Lin
- Center for Soft Matter Research, Department of Physics, New York University, New York, New York 10003, USA
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Ivane Jorjadze
- Center for Soft Matter Research, Department of Physics, New York University, New York, New York 10003, USA
| | - Lea-Laetitia Pontani
- Center for Soft Matter Research, Department of Physics, New York University, New York, New York 10003, USA
- Institut des Nanosciences de Paris, UMR 7588-CNRS/Universite Pierre et Marie Curie, 75005 Paris, France
| | - Matthieu Wyart
- Physics Institute, Ecole Polytechnique Federale de Lausanne, 1015 Lausanne, Switzerland
| | - Jasna Brujic
- Center for Soft Matter Research, Department of Physics, New York University, New York, New York 10003, USA
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42
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Gratale MD, Ma X, Davidson ZS, Still T, Habdas P, Yodh AG. Vibrational properties of quasi-two-dimensional colloidal glasses with varying interparticle attraction. Phys Rev E 2016; 94:042606. [PMID: 27841543 DOI: 10.1103/physreve.94.042606] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Indexed: 06/06/2023]
Abstract
We measure the vibrational modes and particle dynamics of quasi-two-dimensional colloidal glasses as a function of interparticle interaction strength. The interparticle attractions are controlled via a temperature-tunable depletion interaction. Specifically, the interparticle attraction energy is increased gradually from a very small value (nearly hard-sphere) to moderate strength (∼4k_{B}T), and the variation of colloidal particle dynamics and vibrations are concurrently probed. The particle dynamics slow monotonically with increasing attraction strength, and the particle motions saturate for strengths greater than ∼2k_{B}T, i.e., as the system evolves from a nearly repulsive glass to an attractive glass. The shape of the phonon density of states is revealed to change with increasing attraction strength, and the number of low-frequency modes exhibits a crossover for glasses with weak compared to strong interparticle attraction at a threshold of ∼2k_{B}T. This variation in the properties of the low-frequency vibrational modes suggests a new means for distinguishing between repulsive and attractive glass states.
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Affiliation(s)
- Matthew D Gratale
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Xiaoguang Ma
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Complex Assemblies of Soft Matter, CNRS-Solvay-UPenn UMI 3254, Bristol, Pennsylvania 19007-3624, USA
| | - Zoey S Davidson
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Tim Still
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Piotr Habdas
- Department of Physics, Saint Joseph's University, Philadelphia, Pennsylvania 19131, USA
| | - A G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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43
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Yang X, Liu R, Yang M, Wang WH, Chen K. Structures of Local Rearrangements in Soft Colloidal Glasses. PHYSICAL REVIEW LETTERS 2016; 116:238003. [PMID: 27341261 DOI: 10.1103/physrevlett.116.238003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Indexed: 06/06/2023]
Abstract
We image local structural rearrangements in soft colloidal glasses under small periodic perturbations induced by thermal cycling. Local structural entropy S_{2} positively correlates with observed rearrangements in colloidal glasses. The high S_{2} values of the rearranging clusters in glasses indicate that fragile regions in glasses are structurally less correlated, similar to structural defects in crystalline solids. Slow-evolving high S_{2} spots are capable of predicting local rearrangements long before the relaxations occur, while fluctuation-created high S_{2} spots best correlate with local deformations right before the rearrangement events. Local free volumes are also found to correlate with particle rearrangements at extreme values, although the ability to identify relaxation sites is substantially lower than S_{2}. Our experiments provide an efficient structural identifier for the fragile regions in glasses and highlight the important role of structural correlations in the physics of glasses.
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Affiliation(s)
- Xiunan Yang
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Rui Liu
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Mingcheng Yang
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Wei-Hua Wang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Ke Chen
- Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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44
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Mizuno H, Saitoh K, Silbert LE. Elastic moduli and vibrational modes in jammed particulate packings. Phys Rev E 2016; 93:062905. [PMID: 27415345 DOI: 10.1103/physreve.93.062905] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Indexed: 06/06/2023]
Abstract
When we elastically impose a homogeneous, affine deformation on amorphous solids, they also undergo an inhomogeneous, nonaffine deformation, which can have a crucial impact on the overall elastic response. To correctly understand the elastic modulus M, it is therefore necessary to take into account not only the affine modulus M_{A}, but also the nonaffine modulus M_{N} that arises from the nonaffine deformation. In the present work, we study the bulk (M=K) and shear (M=G) moduli in static jammed particulate packings over a range of packing fractions φ. The affine M_{A} is determined essentially by the static structural arrangement of particles, whereas the nonaffine M_{N} is related to the vibrational eigenmodes. We elucidate the contribution of each vibrational mode to the nonaffine M_{N} through a modal decomposition of the displacement and force fields. In the vicinity of the (un)jamming transition φ_{c}, the vibrational density of states g(ω) shows a plateau in the intermediate-frequency regime above a characteristic frequency ω^{*}. We illustrate that this unusual feature apparent in g(ω) is reflected in the behavior of M_{N}: As φ→φ_{c}, where ω^{*}→0, those modes for ω<ω^{*} contribute less and less, while contributions from those for ω>ω^{*} approach a constant value which results in M_{N} to approach a critical value M_{Nc}, as M_{N}-M_{Nc}∼ω^{*}. At φ_{c} itself, the bulk modulus attains a finite value K_{c}=K_{Ac}-K_{Nc}>0, such that K_{Nc} has a value that remains below K_{Ac}. In contrast, for the critical shear modulus G_{c}, G_{Nc} and G_{Ac} approach the same value so that the total value becomes exactly zero, G_{c}=G_{Ac}-G_{Nc}=0. We explore what features of the configurational and vibrational properties cause such a distinction between K and G, allowing us to validate analytical expressions for their critical values.
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Affiliation(s)
- Hideyuki Mizuno
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Kuniyasu Saitoh
- Faculty of Engineering Technology, MESA+, University of Twente, 7500 AE Enschede, The Netherlands
| | - Leonardo E Silbert
- Department of Physics, Southern Illinois University Carbondale, Carbondale, Illinois 62901, USA
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45
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Wei WS, Gharbi MA, Lohr MA, Still T, Gratale MD, Lubensky TC, Stebe KJ, Yodh AG. Dynamics of ordered colloidal particle monolayers at nematic liquid crystal interfaces. SOFT MATTER 2016; 12:4715-4724. [PMID: 27109759 DOI: 10.1039/c6sm00295a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We prepare two-dimensional crystalline packings of colloidal particles on surfaces of the nematic liquid crystal (NLC) 5CB, and we investigate the diffusion and vibrational phonon modes of these particles using video microscopy. Short-time particle diffusion at the air-NLC interface is well described by a Stokes-Einstein model with viscosity similar to that of 5CB. Crystal phonon modes, measured by particle displacement covariance techniques, are demonstrated to depend on the elastic constants of 5CB through interparticle forces produced by LC defects that extend from the interface into the underlying bulk material. The displacement correlations permit characterization of transverse and longitudinal sound velocities of the crystal packings, as well as the particle interactions produced by the LC defects. All behaviors are studied in the nematic phase as a function of increasing temperature up to the nematic-isotropic transition.
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Affiliation(s)
- Wei-Shao Wei
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Mohamed Amine Gharbi
- Department of Physics, McGill University, Montreal, Quebec, Canada and Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Matthew A Lohr
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Tim Still
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Matthew D Gratale
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - T C Lubensky
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
| | - Kathleen J Stebe
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - A G Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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46
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Schindler M, Maggs AC. The range and nature of effective interactions in hard-sphere solids. SOFT MATTER 2016; 12:2612-2622. [PMID: 26830000 DOI: 10.1039/c6sm00032k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Colloidal systems observed in video microscopy are often analysed using the displacements correlation matrix of particle positions. In non-thermal systems, the inverse of this matrix can be interpreted as a pair-interaction potential between particles. If the system is thermally agitated, however, only an effective interaction is accessible from the correlation matrix. We show how this effective interaction differs from the non-thermal case by comparing with high-statistics numerical data from hard-sphere crystals.
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Affiliation(s)
- Michael Schindler
- UMR Gulliver 7083 CNRS, ESPCI ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
| | - A C Maggs
- UMR Gulliver 7083 CNRS, ESPCI ParisTech, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
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47
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Karmakar S, Dasgupta C, Sastry S. Short-Time Beta Relaxation in Glass-Forming Liquids Is Cooperative in Nature. PHYSICAL REVIEW LETTERS 2016; 116:085701. [PMID: 26967425 DOI: 10.1103/physrevlett.116.085701] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Indexed: 05/17/2023]
Abstract
Temporal relaxation of density fluctuations in supercooled liquids near the glass transition occurs in multiple steps. Using molecular dynamics simulations for three model glass-forming liquids, we show that the short-time β relaxation is cooperative in nature. Using finite-size scaling analysis, we extract a growing length scale associated with beta relaxation from the observed dependence of the beta relaxation time on the system size. We find, in qualitative agreement with the prediction of the inhomogeneous mode coupling theory, that the temperature dependence of this length scale is the same as that of the length scale that describes the spatial heterogeneity of local dynamics in the long-time α-relaxation regime.
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Affiliation(s)
- Smarajit Karmakar
- Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
| | - Chandan Dasgupta
- Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India
- Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
| | - Srikanth Sastry
- Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, India
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Shen H, Tan P, Xu L. Probing the Role of Mobility in the Collective Motion of Nonequilibrium Systems. PHYSICAL REVIEW LETTERS 2016; 116:048302. [PMID: 26871359 DOI: 10.1103/physrevlett.116.048302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Indexed: 06/05/2023]
Abstract
By systematically varying the mobility of self-propelled particles in a 2D lattice, we experimentally study the influence of particle mobility on system's collective motion. Our system is intrinsically nonequilibrium due to the lack of energy equipartition. By constructing the covariance matrix of spatial fluctuations and solving for its eigenmodes, we obtain the collective motions of the system with various magnitudes. Interestingly, our structurally ordered nonequilibrium system exhibits properties almost identical to disordered glassy systems under thermal equilibrium: the modes with large overall motions are spatially correlated and quasilocalized while the modes with small collective motions are highly localized, resembling the low- and high-frequency modes in glass. More surprisingly, a peak similar to the boson peak forms in our nonequilibrium system as the number of mobile particles increases, revealing the possible origin of the boson peak from a dynamic aspect. We further illustrate that the spatially correlated large-movement modes can be produced by the cooperation of highly active particles above a threshold fraction, while the localized small-movement modes can be created by adding individual inactive particles. Our study clarifies the role of mobility in collective motions, and further suggests a promising possibility of extending the powerful mode analysis approach to nonequilibrium systems.
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Affiliation(s)
- Hongchuan Shen
- Department of Physics, The Chinese University of Hong Kong, Hong Kong, China
| | - Peng Tan
- Department of Physics, The Chinese University of Hong Kong, Hong Kong, China
- Department of Physics, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
| | - Lei Xu
- Department of Physics, The Chinese University of Hong Kong, Hong Kong, China
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Karmakar S, Dasgupta C, Sastry S. Length scales in glass-forming liquids and related systems: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:016601. [PMID: 26684508 DOI: 10.1088/0034-4885/79/1/016601] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The central problem in the study of glass-forming liquids and other glassy systems is the understanding of the complex structural relaxation and rapid growth of relaxation times seen on approaching the glass transition. A central conceptual question is whether one can identify one or more growing length scale(s) associated with this behavior. Given the diversity of molecular glass-formers and a vast body of experimental, computational and theoretical work addressing glassy behavior, a number of ideas and observations pertaining to growing length scales have been presented over the past few decades, but there is as yet no consensus view on this question. In this review, we will summarize the salient results and the state of our understanding of length scales associated with dynamical slow down. After a review of slow dynamics and the glass transition, pertinent theories of the glass transition will be summarized and a survey of ideas relating to length scales in glassy systems will be presented. A number of studies have focused on the emergence of preferred packing arrangements and discussed their role in glassy dynamics. More recently, a central object of attention has been the study of spatially correlated, heterogeneous dynamics and the associated length scale, studied in computer simulations and theoretical analysis such as inhomogeneous mode coupling theory. A number of static length scales have been proposed and studied recently, such as the mosaic length scale discussed in the random first-order transition theory and the related point-to-set correlation length. We will discuss these, elaborating on key results, along with a critical appraisal of the state of the art. Finally we will discuss length scales in driven soft matter, granular fluids and amorphous solids, and give a brief description of length scales in aging systems. Possible relations of these length scales with those in glass-forming liquids will be discussed.
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Affiliation(s)
- Smarajit Karmakar
- TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
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Abstract
We report an analytical study of the vibrational spectrum of the simplest model of jamming, the soft perceptron. We identify two distinct classes of soft modes. The first kind of modes are related to isostaticity and appear only in the close vicinity of the jamming transition. The second kind of modes instead are present everywhere in the glass phase and are related to the hierarchical structure of the potential energy landscape. Our results highlight the universality of the spectrum of normal modes in disordered systems, and open the way toward a detailed analytical understanding of the vibrational spectrum of low-temperature glasses.
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