Huang Tai-Chieh, Chen Yen-Yu, Chu Chih-Chien, Hsiao Vincent K S
Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Nantou 54561, Taiwan.
Graduate Program of Optoelectronic Technology, National Chi Nan University, Nantou 54561, Taiwan.
Materials (Basel). 2015 Sep 11;8(9):6071-6084. doi: 10.3390/ma8095293.
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 -to- 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 - 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.
通过使用不同的偶氮苯(Azo)衍生物和激光波长,对胆甾相液晶(CLC)的激光引发热(光热)开关特性进行了表征。在405纳米激光照射下,掺杂偶氮苯的胆甾相液晶发生从胆甾相到各向同性的相变。当405纳米激光照射被阻断时,不会发生光异构化,因为只使用了单一激光。由于系统的光热效应,掺杂偶氮苯的胆甾相液晶在405纳米激光的开-关切换下具有快速响应。在蒽醌(AQ)-偶氮苯掺杂的胆甾相液晶中,使用不能用于产生偶氮苯光异构化的660纳米激光来研究掺杂偶氮苯的光热效应。结果表明,在偶氮苯部分邻位带有两个甲基的类液晶偶氮苯衍生物(A4)可以大大降低清亮点温度,并在AQ-A4掺杂的胆甾相液晶中产生大量热量。