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Related papers: The Geometry of the Cholesteric Phase

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Polar nematic liquid crystals are new classes of condensed-matter states where the inversion symmetry common to the traditional apolar nematics is broken. Establishing theoretical descriptions for the novel phase states is an urgent task.…

Soft Condensed Matter · Physics 2024-02-01 Yu Zou , Satoshi Aya

We present a theoretical study of the director fields and energetics of nematic liquid crystal shells with two pairs of surface defects. The pairs of defects can undergo abrupt transitions between a configuration of maximum separation to at…

Soft Condensed Matter · Physics 2012-11-21 V. Koning , T. Lopez-Leon , A. Fernandez-Nieves , V. Vitelli

We generalize the shape optimization problem for the existence of stable equilibrium configurations of nematic and cholesteric liquid crystal drops surrounded by an isotropic solution to include a broader family of admissible domains with…

Analysis of PDEs · Mathematics 2024-08-29 Alessandro Giacomini , Silvia Paparini

The billiard problem of statistical physics is considered in a new geometric approach with a symmetric phase space. The structure and topological features of typical billiard phase portrait are defined. The connection between geometric,…

Chaotic Dynamics · Physics 2007-05-23 Sergey V. Naydenov , Vladimir V. Yanovsky

Cholesteric Liquid Crystals (CLCs), subject to externally applied magnetic fields and confined between two parallel planar surfaces with strong homeotropic anchoring conditions, are found to undergo transitions to different types of…

Soft Condensed Matter · Physics 2019-11-28 G. De Matteis , L. Martina , C. Naya , V. Turco

We theoretically investigate under what conditions the director field in a spindle-shaped nematic droplet or tactoid obtains a twisted, parity-broken structure. By minimizing the sum of the bulk elastic and surface energies, we show that a…

Soft Condensed Matter · Physics 2016-08-31 P. Prinsen , P. van der Schoot

We give a description of the intrinsic geometry of elastic distortions in three-dimensional nematic liquid crystals and establish necessary and sufficient conditions for a set of functions to represent these distortions by describing how…

Soft Condensed Matter · Physics 2021-06-28 Joseph Pollard , Gareth P. Alexander

We show that topological phases include disordered materials if the underlying invariant is interpreted as originating from coarse geometry. This coarse geometric framework, grounded in physical principles, offers a natural setting for the…

Disordered Systems and Neural Networks · Physics 2025-04-08 Christoph S. Setescak , Caio Lewenkopf , Matthias Ludewig

One of the central experimental efforts in nematic colloids research aims to explore how the interplay between the geometry of particles along with the accompanying nematic director deformations and defects around them can provide a means…

Soft Condensed Matter · Physics 2016-12-28 Bohdan Senyuk , Manoj B. Pandey , Qingkun Liu , Mykola Tasinkevych , Ivan I. Smalyukh

There is considerable interest in understanding and controlling topological defects in nematic liquid crystals (LCs). Confinement, in the form of droplets, has been particularly effective in that regard. Here, we employ the Landau-de Gennes…

Even though chiral nematic phases were the first liquid crystals experimentally observed more than a century ago, the origin of the thermodynamic stability of cholesteric states is still unclear. In this Letter we address the problem by…

Soft Condensed Matter · Physics 2014-09-05 S. Belli , S. Dussi , M. Dijkstra , R. van Roij

In this paper we explore the mathematical structure of hierarchical organization in smooth dynamical systems. We start by making precise what we mean by a level in a hierarchy, and how the higher le vels need to respect the dynamics on the…

Mathematical Physics · Physics 2007-05-23 Martin Nilsson Jacobi

Thin nematic elastomers, composite hydrogels and plant tissues are among many systems that display uniform anisotropic deformation upon external actuation. In these materials, the spatial orientation variation of a local director field…

Soft Condensed Matter · Physics 2019-09-25 Itay Griniasty , Hillel Aharoni , Efi Efrati

We point out that the smectic-nematic phase transition may considered as a transition of a stack of membranes in $2+\epsilon$ dimensions, in which the layers become so wrinkled that they interpenetrate each other are no longer…

Condensed Matter · Physics 2009-10-31 H. Kleinert

Phase behaviours of liquid crystals under external fields, conjugate to the nematic order and smectic order, are studied within the framework of mean field approximation developed by McMillan. It is found that phase diagrams, of temperature…

Soft Condensed Matter · Physics 2009-11-10 Masashi Torikai , Mamoru Yamashita

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

We theoretically investigate the pitch of lyotropic cholesteric phases composed of slender rods with steric chirality transmitted via a weak helical deformation of the backbone. In this limit, the model is amenable to analytical treatment…

Soft Condensed Matter · Physics 2015-10-28 H. H. Wensink , L. Morales-Anda

We study the smectic $A$-$C$ phase transition in biaxial disordered environments, e.g. fully anisotropic aerogel. We find that both the $A$ and $C$ phases belong to the universality class of the "XY Bragg glass", and therefore have…

Soft Condensed Matter · Physics 2015-06-03 Leiming Chen , John Toner

By molecular modeling we demonstrate that the nematic long-range order discovered in bent-core liquid crystal systems should reveal further spatially homogeneous phases. Two of them are identified as a tetrahedratic nematic ($N_T$) phase…

Soft Condensed Matter · Physics 2009-04-30 Lech Longa , Grzegorz Pająk , Thomas Wydro

We present a phase-field model for simulating the solid-state dewetting of anisotropic crystalline films on non-planar substrates. This model exploits two order parameters to trace implicitly the crystal free surface and the substrate…

Mesoscale and Nanoscale Physics · Physics 2025-05-01 Emma Radice , Marco Salvalaglio , Roberto Bergamaschini