Enhancement of the recording stability of a photorefractive polymer composite by the introduction of a trapping layer

A photorefractive polymer composite containing a trapping layer which exhibits a significant enhancement in its photorefractivity is reported. The photorefractive polymer composite containing a trapping layer showed a grating life time as high as 600 s, while the grating life time was only 7 s in the photorefractive polymer composite without a trapping layer. The grating growth rate was found to be unaffected by the introduction of a trapping layer. The diffraction efficiency and gain coefficient also increased by the introduction of a trapping layer. The enhancement in the photorefractive properties is due to the increase in the space-charge field developed in the photorefractive polymer composite containing a trapping layer.