Interdisciplinary Graduate School of Engineering Sciences, Kyushu University
Abstract
Photo-crosslinkable polymer and dyes containing cinnamoyl groups were available for poled polymer films with stable second-order optical nonlinearity. We prepared poled polymer films using a photo-croslinkable polymer polyvinylcinnamate (PVCN) and three AZO dyes: noncrosslinkable DR1, monocrosslinkable DR2, and bicrosslinkable AZO2. Dye doped PVCN polymer films were crosslinked by UV irradiation at 293K under poling field. In the crosslinked films, small and rapid decrease of second-order nonlinearity was observed in several minutes after poling field was removed. After the first small decrease, however, the crosslinked polymer films exhibited stable second-order optical nonlinearity compared with uncrosslinked films. Further, the stability of second-order optical nonlinearity depended on number of cinnamoyl groups of doped azo dye; the stability was enhanced with increasing number of cinllamoyl group
