arXiv: Soft Condensed Matter最新文献_第3页

Aging in a mean field elastoplastic model of amorphous solids 非晶固体平均场弹塑性模型的时效

arXiv: Soft Condensed Matter Pub Date : 2020-10-06 DOI: 10.1063/5.0033196

J. Parley, S. Fielding, Peter Sollich

{"title":"Aging in a mean field elastoplastic model of amorphous solids","authors":"J. Parley, S. Fielding, Peter Sollich","doi":"10.1063/5.0033196","DOIUrl":"https://doi.org/10.1063/5.0033196","url":null,"abstract":"We construct a mean-field elastoplastic description of the dynamics of amorphous solids under arbitrary time-dependent perturbations, building on the work of Lin and Wyart (2016) for steady shear. Local stresses are driven by power-law distributed mechanical noise from yield events throughout the material, in contrast to the well-studied Hebraud-Lequeux model where the noise is Gaussian. We first use a mapping to a mean first passage time problem to study the phase diagram in the absence of shear, which shows a transition between an arrested and a fluid state. We then introduce a boundary layer scaling technique for low yield rate regimes, which we first apply to study the scaling of the steady state yield rate on approaching the arrest transition. These scalings are further developed to study the aging behaviour in the glassy regime, for different values of the exponent $mu$ characterizing the mechanical noise spectrum. We find that the yield rate decays as a power-law for $1<mu<2$, a stretched exponential for $mu=1$ and an exponential for $mu<1$, reflecting the relative importance of far-field and near-field events as the range of the stress propagator is varied. Comparison of the mean-field predictions with aging simulations of a lattice elastoplastic model shows excellent quantitative agreement, up to a simple rescaling of time.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"117 14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86467708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

Ionically Charged Topological Defects in Nematic Fluids 向列流体中的离子带电拓扑缺陷

arXiv: Soft Condensed Matter Pub Date : 2020-10-01 DOI: 10.1103/PHYSREVX.11.011054

J. Everts, M. Ravnik

{"title":"Ionically Charged Topological Defects in Nematic Fluids","authors":"J. Everts, M. Ravnik","doi":"10.1103/PHYSREVX.11.011054","DOIUrl":"https://doi.org/10.1103/PHYSREVX.11.011054","url":null,"abstract":"Charge profiles in liquid electrolytes are of crucial importance for applications, such as supercapacitors, fuel cells, batteries, or the self-assembly of particles in colloidal or biological settings. However, creating localised (screened) charge profiles in the bulk of such electrolytes, generally requires presence of surfaces -for example provided by colloidal particles or outer surfaces of the material, - which poses a fundamental constraint on the material design. Here, we show that topological defects in nematic electrolytes can perform as regions for local charge separation, forming charged defect cores and in some geometries even electric multilayers, as opposed to the electric double layers found in isotropic electrolytes. Using a Landau-de Gennes-Poisson-Boltzmann theoretical framework, we show that ions highly effectively couple with the topological defect cores via ion solvability, and with the local director-field distortions of the defects via flexoelectricity. The defect charging is shown for different defect types -- lines, points and walls -- using geometries of ionically screened flat IN interfaces, radial hedgehog point defects and half-integer wedge disclinations in the bulk and as stabilised by (charged) colloidal particles. More generally, our findings are relevant for possible applications where topological defects act as diffuse ionic capacitors or as ionic charge carriers.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89208322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

What is the stiffness of a bent book? 一本弯曲的书的硬度是多少?

arXiv: Soft Condensed Matter Pub Date : 2020-09-18 DOI: 10.26226/morressier.5f5f8e69aa777f8ba5bd6086

Samuel Poincloux, Tian Chen, B. Audoly, P. Reis

引用次数: 0

Kosterlitz-Thouless-type caging-uncaging transition in a quasi-one-dimensional hard disk system 准一维硬盘系统的kosterlitz - thoulless型笼-开笼跃迁

arXiv: Soft Condensed Matter Pub Date : 2020-09-02 DOI: 10.1103/PHYSREVRESEARCH.2.033351

A. Huerta, T. Bryk, V. Pergamenshchik, A. Trokhymchuk

引用次数: 12

Self-assembly in rod/coil block copolymers: Degenerate behavior under nonconfinement 棒/线圈嵌段共聚物的自组装:非约束下的简并行为

arXiv: Soft Condensed Matter Pub Date : 2020-09-01 DOI: 10.5488/CMP.23.33603

X.-G. Han, N. Liang, H. Zhang

{"title":"Self-assembly in rod/coil block copolymers: Degenerate behavior under nonconfinement","authors":"X.-G. Han, N. Liang, H. Zhang","doi":"10.5488/CMP.23.33603","DOIUrl":"https://doi.org/10.5488/CMP.23.33603","url":null,"abstract":"The self-assembly of block copolymers containing rigid blocks have received abiding attention due to its rich phase behavior and potential for use in a variety of applications. In this work, under asymmetric interactions between rod/coil components, the self-assembly of coil/coil/rod ABC triblock copolymers is studied using self-consistent field of lattice model. In addition to micelles, centrosymmetric lamellae (CSLM), lamellae, perforated lamellae, strips and gyroids, non-centrosymmetric (NCSLM) lamellae and wavy morphologies are observed as stable phases. The phase diagram of interaction between rod and coil components versus the rod fraction is constructed given a fixed interaction between coil components. For intermediate rod fraction, degenerate behavior is observed. NCSLM and CSLM are degenerate structures. It is found that the entropy of chain conformation plays an important role for this rich behavior. A mechanism of the degenerate behavior is proposed in coil/rod block copolymers under noncofinement. This study provides some new insights into the degenerate behavior of block compolymers, which can offer a theoretical reference for related experiments.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84994985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Dynamics of an acoustically trapped sphere in beating sound waves 振动声波中声捕获球的动力学

arXiv: Soft Condensed Matter Pub Date : 2020-08-29 DOI: 10.1103/PHYSREVRESEARCH.3.013079

Mohammed A. Abdelaziz, D. Grier

引用次数: 4

Stress correlations in frictional granular media 摩擦颗粒介质中的应力相关性

arXiv: Soft Condensed Matter Pub Date : 2020-08-29 DOI: 10.1103/PHYSREVB.103.054110

A. Lemaître, C. Mondal, I. Procaccia, Saikat Roy

{"title":"Stress correlations in frictional granular media","authors":"A. Lemaître, C. Mondal, I. Procaccia, Saikat Roy","doi":"10.1103/PHYSREVB.103.054110","DOIUrl":"https://doi.org/10.1103/PHYSREVB.103.054110","url":null,"abstract":"This paper investigates whether in frictional granular packings, like in Hamiltonian amorphous elastic solids, the stress autocorrelation matrix presents long range anisotropic contributions just as elastic Green's functions. We find that in a standard model of frictional granular packing this is not the case. We prove quite generally that mechanical balance and material isotropy constrain the stress auto-correlation matrix to be fully determined by two spatially isotropic functions: the pressure and torque auto-correlations. The pressure and torque fluctuations being respectively normal and hyperuniform force the stress autocorrelation to decay as the elastic Green's function. Since we find the torque fluctuations to be hyper-uniform, the culprit is the pressure whose fluctuations decay slower than normally as a function of the system's size. Investigating the reason for these abnormal pressure fluctuations we discover that anomalous correlations build up already during the compression of the dilute system before jamming. Once jammed these correlations remain frozen. Whether this is true for frictional matter in general or is it the consequence of the model properties is a question that must await experimental scrutiny and possible alternative models.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82030867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Smecticlike rheology and pseudolayer compression elastic constant of a twist-bend nematic liquid crystal 扭弯向列液晶的微晶流变性和伪层压缩弹性常数

arXiv: Soft Condensed Matter Pub Date : 2020-08-24 DOI: 10.1103/PHYSREVMATERIALS.4.115601

M. P. Kumar, P. Kula, S. Dhara

{"title":"Smecticlike rheology and pseudolayer compression elastic constant of a twist-bend nematic liquid crystal","authors":"M. P. Kumar, P. Kula, S. Dhara","doi":"10.1103/PHYSREVMATERIALS.4.115601","DOIUrl":"https://doi.org/10.1103/PHYSREVMATERIALS.4.115601","url":null,"abstract":"In twist-bend nematic (Ntextsubscript{TB}) liquid crystals (LCs), the mean molecular orientation exhibits heliconical structure with nanoscale periodicity. On the mesoscopic scale, Ntextsubscript{TB} resembles layered systems (like smectics), where the helical pitch is equivalent to \"pseudo-layers\" without a true mass density wave. We study rheological properties of a Ntextsubscript{TB} phase and compare the results with those of an usual SmA phase. Analysing the shear response and adapting a simplified physical model for rheology of defect mediated lamellar systems we measure the pseudo-layer compression elastic constant $B_{eff}$ of Ntextsubscript{TB} phase from the measurements of dynamic modulus $G^{*}(omega)$. We find that $B_{eff}$ of the Ntextsubscript{TB} phase is in the range of $10^{3}-10^{6}$ Pa and it follows a temperature dependence, $B_{eff}sim (T_{TB}-T)^{2}$ as predicted by the recent coarse-grained elastic theory. Our results show that the structural rheology of Ntextsubscript{TB} is strikingly similar to that of the usual smectic LCs although the temperature dependence of $B_{eff}$ is much faster than smectic LCs as predicted by the coarse-grained models.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80641509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Structural and mechanical characteristics of sphere packings near the jamming transition: From fully amorphous to quasiordered structures 接近干扰转变的球形填料的结构和力学特性:从完全非晶到准有序结构

arXiv: Soft Condensed Matter Pub Date : 2020-08-22 DOI: 10.1103/physrevmaterials.4.115602

H. Mizuno, Kuniyasu Saitoh, L. Silbert

{"title":"Structural and mechanical characteristics of sphere packings near the jamming transition: From fully amorphous to quasiordered structures","authors":"H. Mizuno, Kuniyasu Saitoh, L. Silbert","doi":"10.1103/physrevmaterials.4.115602","DOIUrl":"https://doi.org/10.1103/physrevmaterials.4.115602","url":null,"abstract":"Mechanically stable sphere packings are generated in three-dimensional space using the discrete element method, which span a wide range in structural order, ranging from fully amorphous to quasi-ordered structures, as characterized by the bond orientational order parameter. As the packing pressure, $p$, varies from the marginally rigid limit at the jamming transition ($p approx 0$) to that of more robust systems ($p gg 0$), the coordination number, $z$, follows a familiar scaling relation with pressure, namely, $Delta z = z - z_c sim p^{1/2}$, where $z_c = 2d = 6$ ($d=3$ is the spatial dimension). While it has previously been noted that $Delta z$ does indeed remain the control parameter for determining the packing properties, here we show how the packing structure plays an influential role on the mechanical properties of the packings. Specifically, we find that the elastic (bulk $K$ and shear $G$) moduli, generically referred to as $M$, become functions of both $Delta z$ and the structure, to the extent that $M-M_c sim Delta z$. Here, $M_c$ are values of the elastic moduli at the jamming transition, which depend on the structure of the packings. In particular, the zero shear modulus, $G_c=0$, is a special feature of fully amorphous packings, whereas more ordered packings take larger, positive values, $G_c > 0$.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"97 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73514073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Level statistics and Anderson delocalization in two-dimensional granular materials 二维颗粒材料中的水平统计和安德森离域

arXiv: Soft Condensed Matter Pub Date : 2020-08-17 DOI: 10.1103/PHYSREVB.103.104201

L. Zhang, Yinqiao Wang, Jie Zheng, Aile Sun, Xulai Sun, Yujie Wang, W. Schirmacher, Jie Zhang

引用次数: 1