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Related papers: Point Defects, Chirality and Singularity Theory in…

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Using particle-resolved molecular-dynamics simulations, we compute the phase diagram for soft repulsive spherocylinders confined on the surface of a sphere. While crystal (K), smectic (Sm), and isotropic (I) phases exhibit a stability…

Soft Condensed Matter · Physics 2025-11-03 Jaydeep Mandal , Hartmut Löwen , Prabal K. Maiti

Circular dichroism (CD), induced by chirality, is an important tool for manipulating light or for characterizing morphology of molecules, proteins, crystals and nano-structures. CD is manifested over a wide size-range, from molecules to…

Chiral nematic or cholesteric liquid crystals (LCs) are mesophases with long-ranged orientational order featuring a quasi-layered periodicity imparted by a helical configuration but lacking positional order. Doping molecular cholesteric LCs…

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

We present a microscopic analysis of the instability of the nematic phase to chirality when molecular chirality is introduced perturbatively. We show that previously neglected short-range biaxial correlations play a crucial role in…

Soft Condensed Matter · Physics 2009-10-28 A. B. Harris , Randall D. Kamien , T. C. Lubensky

We present important new results from light-microscopy and rheometry on a moderately concentrated lyotropic smectic, with and without particulate additives. Shear-treatment aligns the phase rapidly, except for a striking network of…

Soft Condensed Matter · Physics 2015-06-25 Geetha Basappa , Suneel , V. Kumaran , Prabhu R. Nott , Sriram Ramaswamy , V. M. Naik , Deeleep Rout

Crystalline assemblages of identical sub-units packed together and elastically bent in the form of a torus have been found in the past ten years in a variety of systems of surprisingly different nature, such as viral capsids, self-assembled…

Soft Condensed Matter · Physics 2008-07-29 Luca Giomi , Mark J. Bowick

We show that the number of distinct topological states associated to a given knotted defect, $L$, in a nematic liquid crystal is equal to the determinant of the link $L$. We give an interpretation of these states, demonstrate how they may…

Soft Condensed Matter · Physics 2014-07-11 Thomas Machon , Gareth P. Alexander

We present large scale computer simulations of the nonlinear bulk rheology of lamellar phases (smectic liquid crystals) at moderate to large values of the shear rate (Peclet numbers 10-100), in both two and three dimensions. In two…

Soft Condensed Matter · Physics 2012-03-15 O. Henrich , K. Stratford , D. Marenduzzo , P. V. Coveney , M. E. Cates

The effect of anisotropy on defect mode peculiarities in cholesteric liquid crystals is investigated. The problem is solved by Ambartsumians layer addition modified method. Two cases are considered. In the first case, it is assumed that the…

Optics · Physics 2019-03-20 A. H. Gevorgyan , K. B. Oganesyan

Defects are a ubiquitous feature of ordered media. They have certain universal features, independent of the underlying physical system, reflecting their topological origins. While the topological properties of defects are robust, they…

Soft Condensed Matter · Physics 2021-02-24 Chiqun Zhang , Amit Acharya , Alan C. Newell , Shankar C. Venkataramani

Defects in liquid crystals are of great practical importance and theoretical interest. Despite tremendous efforts, predicting the location and transition of defects under various topological constraint and external field remains to be a…

Soft Condensed Matter · Physics 2014-08-27 Yucheng Hu , Yang Qu , Pingwen Zhang

Emerging technologies based on liquid crystal (LC) materials increasingly leverage the presence of nanoscale defects, unlike the canonical application of LCs -- LC displays. The inherent nanoscale characteristics of LC defects present both…

Soft Condensed Matter · Physics 2017-02-20 Fred Fu , Nasser Mohieddin Abukhdeir

We study the light scattering by localized quasi planar excitations of a Cholesteric Liquid Crystal known as spherulites. Due to the anisotropic optical properties of the medium and the peculiar shape of the excitations, we quantitatively…

Soft Condensed Matter · Physics 2018-10-24 G. De Matteis , D. Delle Side , L. Martina , V. Turco

We theoretically investigate into the effects of the incidence angles in light transmission of cholesteric liquid crystal two-layer sandwich structures with twist defects created by rotation of the one layer about the helical axis.The…

Optics · Physics 2015-05-14 Roman I. Egorov , Alexei D. Kiselev

We experimentally investigate the chiral optical response of an individual nanostructure consisting of three equally sized spherical nanoparticles made of different materials and arranged in \ang{90} bent geometry. Placing the nanostructure…

Optics · Physics 2019-07-30 Sergey Nechayev , René Barczyk , Uwe Mick , Peter Banzer

Polymorphism, the phenomenon that a species can exist in many discrete forms, is common in nature, such as hair colors in an animal species, flower colors in a tree species, and blood types in humans, etc. In materials science, it refers to…

Soft Condensed Matter · Physics 2022-10-26 Khoa V. Le , Michael R. Tuchband , Hiroshi Iwayama , Yoichi Takanishi , Noel A. Clark , Fumito Araoka

Chirality refers to the asymmetry of objects that cannot be superimposed on their mirror image. It is a concept that exists in various scientific fields and has profound consequences. Although these are perhaps most widely recognized within…

The hydrodynamic stresses created by active particles can destabilise orientational order present in the system. This is manifested, for example, by the appearance of a bend instability in active nematics or in quasi-2-dimensional living…

Soft Condensed Matter · Physics 2024-06-05 Bhavesh Gautam , Juho Lintuvuori

Topological defects are singularities within a field that cannot be removed by continuous transformations. The definition of these irregularities requires an ordered reference configuration, calling into question whether they exist in…

Soft Condensed Matter · Physics 2025-01-06 Vinay Vaibhav , Arabinda Bera , Amelia C. Y. Liu , Matteo Baggioli , Peter Keim , Alessio Zaccone