Thermal fixing of holographic gratings in BaTiO(3)

Fixing of a holographic grating in a single BaTiO(3) crystal is studied in detail by means of a thermal process. Above T = 78 °C, oscillations of the diffracted intensity of the sample appear, which are related to the fixing process. Different methods to perform and optimize the fixing process are described. A fixed diffraction efficiency of ~25% was obtained. Self-enhanced as well as self-depleted diffraction from the fixed photorefractive gratings was observed.