Skyrmions in blue phases of chiral liquid crystals

Jaka Pišljar (Author), Matevž Marinčič (Author), Sharmistha Ghosh (Author), Srikanth Turlapati (Author), Nandiraju V. S. Rao (Author), Andriy Nych (Author), Miha Škarabot (Author), Alenka Mertelj (Author), Andrej Petelin (Author), Anja Bregar (Author), Miha Ravnik (Author), Igor Muševič (Author)

Abstract

Using high-resolution microscope observations, we show that both the static cubic (BPI) and the dynamic amorphous (BPIII) blue phases consist of fractional skyrmion filaments that transform into the same quasi two-dimensional structure of ‘baby’ half-skyrmions upon confinement to ultra-thin layers. We confirm this using numerical simulations of BPIII skyrmion structures in confinement combined with optical simulations, which reproduce experimental images, shown to originate at the glass-sample boundaries. Chiral nature of skyrmion filaments is demonstrated through experimental observations and optical simulations using circularly polarised light of opposite handedness producing images that vary strongly in comparative optical contrast. Direct observations and light scattering measurements of BPIII dynamics in bulk reveal that it is a highly dynamic phase, distinguished by two well-separated dynamic regimes, the slower of which can be observed even with a naked eye. We show that the slow dynamics corresponds to the thermally driven collective reshaping of the amorphous structure, while the fast mode is due to the director fluctuations within the filaments. Chirality of the relaxation modes in the bulk isotropic phase is also demonstrated and discussed. We show the dynamics in thinnest layers still show a two phase behaviour, with overall dynamics of half-skyrmions dramatically slowed down.

Keywords

tekoči kristali;kiralni nematiki;modre faze;skirmioni;liquid crystals;chiral nematics;blue phases;skyrmions;

Data

Language:	English
Year of publishing:	2023
Typology:	1.08 - Published Scientific Conference Contribution
Organization:	UL FMF - Faculty of Mathematics and Physics
Publisher:	Taylor & Francis
UDC:	538.9
COBISS:	147562243
ISSN:	1366-5855
Views:	27
Downloads:	5
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	Slovenian
Secondary keywords:	tekoči kristali;kiralni nematiki;modre faze;skirmioni;
Type (COBISS):	Article
Source comment:	Nasl. z nasl. zaslona; Soavtorji: M. Marinčič, S. Ghosh, S. Turlapati, Rao Nandiraju, A. Nych, M. Škarabot, A. Mertelj, A. Petelin, A. Pusovnik, M. Ravnik, I. Muševič; Opis vira z dne 10. 1. 2024;
Pages:	str. 1406–1425
Volume:	ǂVol. ǂ50
Issue:	ǂiss. ǂ7/10
Chronology:	2023
DOI:	10.1080/02678292.2023.2188613
ID:	26375678