Abstract
The laser-initiated thermal (optothermal) switching of cholesteric liquid crystals (CLCs) is characterized by using different azobenzene (Azo) derivatives and laser wavelengths. Under 405-nm laser irradiation, Azo-doped CLCs undergo phase transition from cholesteric to isotropic. No cis-to-trans photoisomerization occurs when the 405-nm laser irradiation is blocked because only a single laser is used. The fast response of Azo-doped CLCs under the on–off switching of the 405-nm laser occurs because of the optothermal effect of the system. The 660-nm laser, which cannot be used as irradiation to generate the trans–cis photoisomerization of Azo, is used in Anthraquinone (AQ)-Azo-doped CLCs to examine the optothermal effect of doped Azo. The results show that the LC-like Azo derivative bearing two methyl groups ortho to the Azo moiety (A4) can greatly lower the clearing temperature and generate large amount of heat in AQ-A4-doped CLCs.
Highlights
Photoresponsive liquid crystals (PLCs) [1], which consist of a photochromic dye and LCs, have attracted the attention of researchers because several optical properties, such as light intensity, polarization, and reflective wavelength, can be modulated or switched by light-induced LC phase changes
The optothermal system of Azo- and AQ-doped cholesteric LCs (CLCs) was characterized, and the results show that the use of suitable Azo helps to decrease the clearing temperature (CT) of CLCs and further facilitates the phase change under laser irradiation
For the A4-doped CLCs, no obvious phase change was observed under optothermal system of Azo- and AQ-doped CLCs was characterized, and the results sho
Summary
Photoresponsive liquid crystals (PLCs) [1], which consist of a photochromic dye and LCs (nematic LCs, cholesteric LCs, and blue phase LCs), have attracted the attention of researchers because several optical properties, such as light intensity, polarization, and reflective wavelength, can be modulated or switched by light-induced LC phase changes. Recent studies have shown that using a single laser beam (405-nm wavelength) can generate an efficient external stimulus to modulate the optical properties from Azo-dye-doped CLCs. The fast on–off response (
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
