Photorefractive hologram written in Fe:LiNbO/sub 3/ at wavelength transmittable through quartz fibers

We report observation of the photorefractive effects in a LiNbOs:Fe crystal at 1.37 /spl mu/m wavelength with two-step recording. In the two-step recording, light at visible frequency excites electrons to an intermediate state, then photons of recording excite them to the conduction band. Our final goal is to generate a hologram with ultrashort pulses at 1.37 /spl mu/m with assist of its SHG pulse, which is accurately synchronized with the signals forming the interferogram.