Stoichiometric LiTaO3 for dynamic holography in near UV wavelength range

LiTaO3 single crystals with near-stoichiometric composition are grown using a double crucible Czochralski method equipped with an automatic powder sup ply system, Their photorefractive properties are compared with those of LiT aO3 crystals grown from the congruent composition melt. Two beam coupling e xperiments show that nearly stoichiometric LiTaO3 crystals exhibit consider ably higher photorefractive gain, speed and sensitivity than conventional c ongruent crystals. Due to the relatively large photoconductivity observed a t near UV wavelengths, stoichiometric crystals are further characterized by small photogalvanic fields, making them very attractive for dynamic hologr aphy in this wavelength range.