Polarization holography 1: A new high-efficiency organic material with reversible photoinduced birefringence

A new organic material for polarization holographic recording--azo-dye methyl-orange, introduced in polyvinyl alcohol (PVA)--is fabricated and investigated. It possesses all the good characteristics of the known polarization-sensitive materials--high sensitivity, reversibility, etc.--but excels them substantially in the magnitude of the photoinduced birefringence: delta n > 10(-3). This makes possible the recording of reversible polarization gratings with diffraction efficiency over 30%. Depending on the conditions of production and subsequent mechanical and thermal treatments the layers of methyl orange/PVA may also have intrinsic birefringence. In this paper the results of experimental investigations into the properties of this new material are reported.