Light-induced photoluminescence switching using liquid crystal-dispersed quantum dots

• Main Authors: Hsiao, Vincent K. S., Prasad, Paras N., Cheng, Min-Chi, Chu, Chih-Chien, Su, Yu-Chuan, Chang, Wei-Ting, Yong, Ken-Tye, Law, Wing-Cheung
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/98951; http://hdl.handle.net/10220/13466
• Institution: Nanyang Technological University

Light-induced photoluminescence (PL) switching using azobenzene-doped liquid crystal (LC)-dispersed quantum dots (QDs) is demonstrated in a format of LC cell and LC-infiltrated tube. Before light irradiation, excitation photons undergo multiple scattering events before emission out of the LC cell, and PL intensity is high. Upon the light irradiation, the trans-to-cis photoisomerization of azobenzene makes the QD-dispersed LCs highly transparent, thus allowing most excitation photons to pass through LCs and decrease PL intensity. This demonstration may allow a new modulating technique for future development of light-switchable, QD-emission-based display or photonic devices.