Resonance running hologram velocity nonlinearity dependence upon light intensity in photorefractive crystals

摘要

We report on the nonlinear relation between the resonance hologram velocity and the recording light irradiance in fringe-locked running hologram experiments carried out on a nominally undoped photorefractive Bi_(12)TiO_(20) crystal using 532 nm wavelength laser light. Such nonlinearity is due to the dependence of the material diffusion length on the light irradiance. Experimental data show a good agreement with the theoretical equations thus supporting the mathematical model here reported and allowing to compute the quantum efficiency for photoelectron generation, the dependence of the diffusion length upon the recorded light irradiance, and the far from saturation diffusion length.