Electro-optic response of polymer-stabilized cholesteric liquid crystals with different polymer concentrations

Saadaoui, Lotfi (author), Yang, Donghao (author), Hassan, Faheem (author), Qiu, Ziyang (author), Wang, Yu (author), Fan, Yujie (author), Drevenšek Olenik, Irena (author), Li, Yigang (author), Zhang, Xinzheng (author), Xu, Jingjun (author)

Polymer-stabilized cholesteric liquid crystals (PSCLCs) have emerged as promising candidates for one-dimensional photonic lattices that enable precise tuning of the photonic band gap (PBG). This work systematically investigates the effect of polymer concentrations on the AC electric field-induced tuning of the PBG in PSCLCs, in so doing it explores a range of concentrations and provides new insights into how polymer concentration affects both the stabilization of cholesteric textures and the electro-optic response. We demonstrate that low polymer concentrations (≈3 wt. %) cause a blue shift in the short wavelength band edge, while high concentrations (≈10 wt. %) lead to a contraction and deterioration of the reflection band. Polarization optical microscopy was conducted to confirm the phase transition induced by the application of an electric field. The observations confirm that increased polymer concentration stabilizes the cholesteric texture. Particularly, the highly desired fingerprint texture was stabilized in a sample with 10 wt. % of the polymer, whereas it was unstable for lower polymer concentrations. Additionally, higher polymer concentrations also improved the dissymmetry factor and stability of the lasing emission, with the dissymmetry factor reaching the value of around 2 for samples with 10 wt. % of polymer additive. Our results provide valuable comprehension into the design of advanced PSCLC structures with tunable optical properties, enhancing device performance and paving the way for innovative photonic applications.

• Language: English
• Keywords: liquid crystals, polymers, optics
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication version: Version of Record
• Publication date: 28.08.2024
• Year: 2024
• Number of pages: 18 str.
• Numbering: Vol. 16, iss. 17, art. no. 2436
• PID: 20.500.12556/RUL-160775-65f57d11-30ff-ade7-10e6-7827cb25b6de
• UDC: 538.9
• ISSN on article: 2073-4360
• DOI: 10.3390/polym16172436
• COBISS.SI-ID: 206330371
• Publication date in RUL: 04.09.2024

Record is a part of a journal

• Title: Polymers
• Shortened title: Polymers
• Publisher: MDPI
• ISSN: 2073-4360
• COBISS.SI-ID: 517951257

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: tekoči kristali, polimeri, optika