Open AccessAzobenzene liquid crystalline materials for efficient optical switching with pulsed and/or continuous wave laser beams
Author(s) -
Uladzimir A. Hrozhyk,
Svetlana V. Serak,
Nelson V. Tabiryan,
Landa Hoke,
Diane M. Steeves,
Brian R. Kimball
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.008697
Subject(s) - azobenzene , materials science , nanosecond , optics , laser , liquid crystal , optoelectronics , photochromism , beam (structure) , optical switch , switching time , molecule , nanotechnology , polymer , chemistry , organic chemistry , physics , composite material
This study compares optical switching capabilities of liquid crystal (LC) materials based on different classes of azobenzene dyes. LCs based on molecules containing benzene rings with nearly symmetrical pi-pi conjugation respond more efficiently to a cw beam than to a nanosecond laser pulse and maintain the changes induced by the beam for tens of hours. Using azo dye molecules containing two benzene rings with push-pull pi-pi conjugation we demonstrate high photosensitivity to both a cw beam as well as nanosecond laser pulse with only 1 s relaxation of light-induced changes in material properties. Even faster, 1 ms restoration time is obtained for azo dye molecules containing hetaryl (benzothiazole) ring with enhanced push-pull pi-pi conjugation. These materials respond most efficiently to pulsed excitation while discriminating cw radiation.