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  • Letter
  • Open Access

Uniaxial versus biaxial pathways in one-dimensional cholesteric liquid crystals

Yucen Han, James Dalby, and Apala Majumdar*

Benjamin M. G. D. Carter

Thomas Machon†

  • Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, United Kingdom

  • H.H. Wills Physics Laboratory and Bristol Centre for Functional Nanomaterials, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, United Kingdom

  • H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, United Kingdom

  • *apala.majumdar@strath.ac.uk
  • †t.machon@bristol.ac.uk
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Phys. Rev. Research 4, L032018 – Published 2 August, 2022

DOI: https://doi.org/10.1103/PhysRevResearch.4.L032018

Abstract

Cholesteric liquid crystals exhibit great morphological richness of static metastable states. Understanding the transitions between such states is key for the development of switchable devices. We show, using a quasi-one-dimensional model, that cholesterics exhibit distinct uniaxial and biaxial pathways between distinct minima. We study transitions between different layer numbers and prove, and show, that transition states are distinguished either through splay-mediated untwisting, understood through contact topology, or the presence of biaxiality. Furthermore we characterize a menagerie of additional saddle points that dictate the connectivity of the solution landscape.

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Phys. Rev. Research 4, L032018– Published 2 August, 2022
  • Received 3 December 2021
  • Revised 3 June 2022
  • Accepted 27 June 2022
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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