Photorefractive properties of photochemically modified poly(hydroxy aminoether)

Abstract

The exposure of photosensitive poly(hydroxyaminoether)-based polymer compositions to light leads to the formation of an image with nonlinear optical and photoelectric properties and, hence, photorefractive behavior. Using the holographic birefringence technique, it was shown that the pumping of one of laser beams (signal beam) at the expense of the intensity of another (reference beam) takes place in the photochemically modified regions of the polymer layer. Unlike the majority of the previously studied photorefractive polymeric media, the beam-coupling gain coefficient Γ(cm–1) exceeds the absorption coefficient α(cm–1); i.e., the intensity of the signal beam after passing the layer becomes higher than that before the layer. A net internal gain, i.e. the difference Γ – α, of 117 cm–1is achieved at E0= 26 V/μm. The photorefractive effect is absent from the unexposed areas of the layer.