THIN-FILM PROCESSING OF NLO MATERIALS .1. STUDIES ON RELAXATION BEHAVIOR OF CORONA POLED AROMATIC DIPOLAR MOLECULES IN A POLYMER MATRIX

A number of corona poled guest-host systems have been investigated to elucidate the nature of interaction between the guest and the host molecules, their compatibility and relaxation behaviour. This study has been carried out by examining the relaxation response of the nonlinear optical effects. Styrene/acrylonitrile copolymer was found to be the ideal matrix studied, since the polymer itself relaxes slowly subsequent to poling and it accommodates a wide range of nonlinear optical molecules differing in molecular structure and polarity. Retention of the second-harmonic intensity has been emphasized as a measure of the relaxation and decay of the order parameters with time. Absorption characteristics of the poled and the unpoled film are also described.