PHOTOREFRACTIVE PROPERTIES OF 4'-NITROBENZYLIDENE-3-ACETAMINO-4-METHOXYANILINE

Undoped single crystals of the organic electro-optic material 4'-nitrobenzylidene-3-acetamino-4-methoxyaniline were found to show photorefractive effects owing to light-induced charge separation. In two-wave-mixing experiments, beam-coupling gains as high as 2.2 cm-1 and response times as low as 8 s at writing intensities of 130 mW/cm2 were measured at a wavelength lambda = 514.5 nm. An analysis of the experimental data shows that the beam-coupling gain is limited by the electro-optic response of the material, while the response time is characterized by a large optical absorption and a low quantum efficiency for carrier generation.