Phase dispersion in mode-locked neodymium: Glass lasers, part 1. Investigation of the photorefractive effect in iron doped lithium niobate for holographic storage applications, part 2

Time resolved linear interferometry shown to be a technique that measures the phase dispersion of the electric field vector in the ultrashort pulses from a modelocked laser system. The technique was used to analyze the dye mode-locked Nd(3+) glass laser. The results of the measurements indicate a rather rapid change in the phases between modes, and a plot of the phase change as a function of mode frequency was obtained. The photorefractive effect in iron doped lithium niobate was also investigated by means of phase holography for data storage and display applications. A nonlinear dynamic theory was developed for the formation of photorefractive volume phase holograms. This was accomplished by examing the feedback mechanism between the photoexcited free electron density and the photogenerated space charge field. An expression for the diffraction efficiency of an attenuated photorefractive grating was obtained where the refractive index modulation of the grating evolves in time in accordance with the nonlinear dynamic theory.