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The order parameter of the smectic liquid crystal phase is the same as that of a superfluid or superconductor, namely a complex scalar field. We show that the essential difference in boundary conditions between these systems leads to a…

Soft Condensed Matter · Physics 2017-02-08 Randall D. Kamien , Ricardo A. Mosna

We formulate a model for a point defect embedded in a homogeneous multilattice crystal with an empirical interatomic potential interaction. Under a natural, phonon stability assumption we quantify the decay of the long-range elastic fields…

Analysis of PDEs · Mathematics 2016-10-03 Derek Olson , Christoph Ortner

The emergence of new techniques for the fabrication of nematic droplets with nontrivial topology provides new routes for the assembly of responsive devices. Here we perform a numerical study of spherical nematic droplets on fibres. We…

Soft Condensed Matter · Physics 2015-12-30 V. M. O. Batista , N. M. Silvestre , M. M. Telo da Gama

Living materials at different length scales manifest active nematic features such as orientational order, nematic topological defects, and active nematic turbulence. Using numerical simulations we investigate the impact of fluid inertia on…

Soft Condensed Matter · Physics 2022-08-10 Roozbeh Saghatchi , Mehmet Yildiz , Amin Doostmohammadi

We use density-functional theory, of the fundamental-measure type, to study the relative stability of the biaxial nematic phase, with respect to non-uniform phases such as smectic and columnar, in fluids made of hard board-like particles…

Soft Condensed Matter · Physics 2017-09-13 Yuri Martinez-Raton , Szabolcs Varga , Enrique Velasco

We report a theoretical and experimental work on the nematicon in the planar cell containing the nematic liquid crystal with negative dielectric anisotropy, aligned homeotropically in the presence of an externally applied voltage. The…

Optics · Physics 2014-03-13 Jing Wang , Junzhu Chen , Jinlong Liu , Yiheng Li , Qi Guo , Wei Hu , Dayu Li , Yonggang Liu , Li Xuan

Colloids dispersed in nematic liquid crystals form topological composites in which colloid-associated defects mediate interactions while adhering to fundamental topological constraints. Better realising the promise of such materials…

Soft Condensed Matter · Physics 2024-04-16 Louise C. Head , Yair A. G. Fosado , Davide Marenduzzo , Tyler N. Shendruk

In equilibrium hard-rod fluids, and in effective hard-rod descriptions of anisotropic soft-particle systems, the transition from the isotropic (I) phase to the nematic phase (N) is observed above the rod aspect ratio L/D = 3.70 as predicted…

Soft Condensed Matter · Physics 2023-02-22 Jayeeta Chattopadhyay , Sriram Ramaswamy , Chandan Dasgupta , Prabal K. Maiti

The paradigm of spontaneous symmetry breaking encompasses the breaking of the rotational symmetries $O(3)$ of isotropic space to a discrete subgroup, i.e. a three-dimensional point group. The subgroups form a rich hierarchy and allow for…

Statistical Mechanics · Physics 2017-03-01 Ke Liu , Jaakko Nissinen , Josko de Boer , Robert-Jan Slager , Jan Zaanen

Topological defects provide a unifying language to describe how orientational order breaks down in active and living matter. Considering cells as elongated particles confluent, epithelial tissues can be interpreted as nematic fields and its…

We study a class of symmetric critical points in a variational $2D$ Landau - de Gennes model where the state of nematic liquid crystals is described by symmetric traceless $3\times 3$ matrices. These critical points play the role of…

Analysis of PDEs · Mathematics 2016-08-24 Radu Ignat , Luc Nguyen , Valeriy Slastikov , Arghir Zarnescu

The problem of heterogeneous nucleation of second-phase in alloys in the vicinity of elastic defects is considered. The defect can be a dislocation line or a crack tip residing in a crystalline solid. We use the Ginzburg-Landau equation to…

Materials Science · Physics 2011-10-07 Christina Bjerkén , Ali R. Massih

When a simple or complex liquid recedes from a smooth solid substrate it often leaves a homogeneous or structured deposit behind. In the case of a receding non-volatile pure liquid the deposit might be a liquid film or an arrangement of…

Fluid Dynamics · Physics 2014-05-13 Uwe Thiele

We formulate the statistical dynamics of topological defects in the active nematic phase, formed in two dimensions by a collection of self-driven particles on a substrate. An important consequence of the non-equilibrium drive is the…

Soft Condensed Matter · Physics 2018-09-12 Suraj Shankar , Sriram Ramaswamy , M. Cristina Marchetti , Mark J. Bowick

The isotropic to ferroelectric nematic liquid transition had been theoretically studied over one hundred years ago, but its experimental studies are rare. Here we present polarizing optical microscopy studies and theoretical considerations…

Topological defects, which are singular points in a director field, play a major role in shaping active systems. Here, we experimentally study topological defects and the flow patterns around them, that are formed during the highly rapid…

Soft Condensed Matter · Physics 2024-03-20 Victor Yashunsky , Daniel J. G. Pearce , Gil Ariel , Avraham Be'er

Recently, Tavarone et al. (J. Chem. Phys. 143, 114505 (2015)) discussed phase behavior of zig-zag and bow-shaped particles composed of three needles. The authors presented very interesting results of extensive Monte Carlo simulations with…

Soft Condensed Matter · Physics 2018-04-18 Paweł Karbowniczek

Optical birefringence and light absorption measurements reveal four regimes for the thermotropic behavior of a nematogen liquid (7CB) upon sequential filling of parallel-aligned capillaries of 12 nm diameter in a monolithic, mesoporous…

Soft Condensed Matter · Physics 2013-04-08 Patrick Huber , Mark Busch , Sylwia Calus , Andriy V. Kityk

We construct a phenomenological Landau-de Gennes theory for hard colloidal rods by performing an order parameter expansion of the chemical-potential dependent grand potential. By fitting the coefficients to known results of Onsager theory,…

Soft Condensed Matter · Physics 2016-05-20 Jeffrey Everts , Melle Punter , Sela Samin , Paul van der Schoot , René van Roij

We study a minimal model of a system with coexisting nematic and polar orientational orders, where one field tends to order and the other prefers isotropy. For strong coupling, the ordered field aligns the isotropic one, locking their…

Soft Condensed Matter · Physics 2025-01-10 Farzan Vafa , Amin Doostmohammadi