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Title: Topology and bistability in liquid crystal devices

Abstract

We study nematic liquid crystal configurations in a prototype bistable device--the post aligned bistable nematic (PABN) cell. Working within the Oseen-Frank continuum model, we describe the liquid crystal configuration by a unit-vector field n, in a model version of the PABN cell. First, we identify four distinct topologies in this geometry. We explicitly construct trial configurations with these topologies which are used as initial conditions for a numerical solver, based on the finite-element method. The morphologies and energetics of the corresponding numerical solutions qualitatively agree with experimental observations and suggest a topological mechanism for bistability in the PABN cell geometry.

Authors:
 [1];  [2];  [3]; ;  [1]
  1. School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW (United Kingdom)
  2. (United Kingdom)
  3. Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS12 6QZ (United Kingdom)
Publication Date:
OSTI Identifier:
21072432
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevE.75.051703; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CONFIGURATION; FINITE ELEMENT METHOD; LIQUID CRYSTALS; MATHEMATICAL MODELS; MORPHOLOGY; TOPOLOGY; VECTOR FIELDS

Citation Formats

Majumdar, A., Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS12 6QZ, Newton, C. J. P., Robbins, J. M., and Zyskin, M.. Topology and bistability in liquid crystal devices. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.051703.
Majumdar, A., Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS12 6QZ, Newton, C. J. P., Robbins, J. M., & Zyskin, M.. Topology and bistability in liquid crystal devices. United States. doi:10.1103/PHYSREVE.75.051703.
Majumdar, A., Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS12 6QZ, Newton, C. J. P., Robbins, J. M., and Zyskin, M.. Tue . "Topology and bistability in liquid crystal devices". United States. doi:10.1103/PHYSREVE.75.051703.
@article{osti_21072432,
title = {Topology and bistability in liquid crystal devices},
author = {Majumdar, A. and Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS12 6QZ and Newton, C. J. P. and Robbins, J. M. and Zyskin, M.},
abstractNote = {We study nematic liquid crystal configurations in a prototype bistable device--the post aligned bistable nematic (PABN) cell. Working within the Oseen-Frank continuum model, we describe the liquid crystal configuration by a unit-vector field n, in a model version of the PABN cell. First, we identify four distinct topologies in this geometry. We explicitly construct trial configurations with these topologies which are used as initial conditions for a numerical solver, based on the finite-element method. The morphologies and energetics of the corresponding numerical solutions qualitatively agree with experimental observations and suggest a topological mechanism for bistability in the PABN cell geometry.},
doi = {10.1103/PHYSREVE.75.051703},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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  • No abstract prepared.