Relationship between molecular structure and photoinduced surface relief grating formation using azobenzene-based photochromic amorphous molecular materials

Abstract

The relationship between molecular structure and photoinduced surface relief grating (SRG) formation has been investigated by using azobenzene-based photochromic amorphous molecular materials. It was shown that modulation depth of SRG formed by irradiation with two coherent Ar⁺ laser beams (488 nm) becomes larger with increasing glass-transition temperature of the material. However, introduction of bulky substituents at both phenyl groups of the azobenzene moiety was undesirable for photoinduced SRG formation. These results were discussed from the viewpoints of frequency of trans–cis and cis–trans isomerization cycles and fluidity of the material upon irradiation.