Optically Induced Dynamics of Isocyanate Organic Films Containing Azobenzene Chromophores

The photophysical formation of surface relief grating (SRG) was compared between isocyanate-based polymeric and non-polymeric thin films of low molecular weight organics containing azobenzene group. The non-polymeric film forms faster and more efficient surface grating formation than the polymeric film when exposed to an interference pattern of polarized Ar+ laser beams at 488 nm. However, the polymeric materials exhibited higher stability of SRG and orientation of azobenzenes than non-polymeric ones. The relation between the rate of photoinduced surface modulation and orientation of azobenzenes is discussed.