LIGHT-INDUCED NONCENTROSYMMETRY IN ACCEPTOR-DONOR-SUBSTITUTED AZOBENZENE SOLUTIONS

Light-induced noncentrosymmetry was achieved experimentally in accepto r-donor-substituted azobenzene solutions and observed by phase-matched nondegenerate six-wave mixing. The microscopic origin of the induced noncentrosymmetry was found to be orientational hole burning, which wa s distinguished directly with net orientation of molecules by experime ntal observations. The decay time of the induced noncentrosymmetry dep ended on the rotational orientation time of the sample's molecule, whi ch varied linearly with the viscosity of the solvent. (C) 1995 Optical Society of America