Surface waves in photorefractive polymer films

We observed the temporal development of surface waves and investigated their power propagation loss in typical photorefractive polymer films sandwiched between ITO glass substrates. We found that amplified scattered waves generated in a pumped region started to develop into surface waves from a point where they reached the substrate through the self-bending effect. The surface waves propagated over a distance of 1.7 mm, thereby confining the power to a region at a distance of 30 microns from the substrate. Considerable propagation power loss of the surface waves was observed at a low pumping power of the beam; however, the power loss decreased considerably when the beam had high power.