Photorefractive two-beam coupling of time-modulated optical signals in Cu-KNSBN crystals

The interaction between two incident beams in a photorefractive Cu-doped (Cu-KNSBN) crystal is investigated at 632.8nm He-Ne laser wavelength. In addition, the coherent two-wave coupling properties of a photoinduced volume refractive-index phase grating in the presence of amplitude modulation on the signal beam are also experimentally investigated as a function of the intensity ratio of the two incident beams. Some preliminary experimental result are presented for use as a dynamic photorefractive beam-splitter and pulse shaping element in coherent optical communication systems and in optical signal processing.