Running streams of a ferroelectric nematic liquid crystal on a lithium niobate surface

Cmok, Luka (author), Coda, Virginie (author), Sebastián Ugarteche, Nerea (author), Mertelj, Alenka (author), Zgonik, Marko (author), Aya, Satoshi (author), Huang, Mingjun (author), Montemezzani, Germano (author), Drevenšek Olenik, Irena (author)

Sessile droplets of a ferroelectric nematic liquid crystalline material were exposed to surface electric fields produced by pyroelectric and photogalvanic (photovoltaic) effects in X-cut iron-doped lithium niobate crystals. The resulting dynamic processes were monitored by polarisation optical (video)microscopy (POM). During heating/cooling cycles, at first, the droplets change their shape from spherical to extended ellipsoidal. Then, they start to move rapidly along the surface electric field, i.e. along the crystal’s polar axis (c-axis). During this motion, several droplets merge into running streams (tendrils) extending towards the edges of the top surface area. Finally, practically all liquid crystalline material is transported from the top surface to the side surfaces of the crystal. At stabilised temperatures, laser illumination of the assembly causes dynamic processes that are localised to the illuminated area. Also, in this case, the LC droplets merge into several tendril-like formations that are preferentially oriented along the c-axis of the crystal. The pattern of tendrils fluctuates with time, but it persists as long as the illumination is present. In this case, the LC material is transported between the central and the edge regions of the illuminated area.

• Language: English
• Keywords: condensed matter physics, ferroelectric nematic liquid crystals, electric field, liquid crystals, ferroelectric nematic phase, interaction with the electric field, dynamic phenomena
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2023
• Number of pages: Str. 1478–1485
• Numbering: Vol. 50, no. 7/10
• PID: 20.500.12556/RUL-152839
• UDC: 538.9
• ISSN on article: 0267-8292
• DOI: 10.1080/02678292.2022.2161018
• COBISS.SI-ID: 136331779
• Publication date in RUL: 08.12.2023

Record is a part of a journal

• Title: Liquid crystals
• Shortened title: Liq. cryst.
• Publisher: Taylor & Francis
• ISSN: 0267-8292
• COBISS.SI-ID: 1690628

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: fizika kondenzirane snovi, feroelektrični nematski tekoči kristali, električno polje

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P1-0192
• Name: Svetloba in snov

• Funder: ARRS - Slovenian Research Agency
• Project number: BI-FR/19-20-PROTEUS-002