Abstract

Optimization of Bi₁₂Ge O₂₀ (BGO) for better photorefractive performance requires a systematic physico-chemical and physical characterization in parallel with material processing, investigation of photorefractive properties and implementation of nonlinear experiments. A main aspect is to analyze the effects of unintentional and intentional doping. We are concerned by the physical characterization of defects. To this end we use novel special thermal and optical spectroscopic methods (1). These survey techniques allow to probe the forbidden gap and to monitor changes in the nature and concentration of the species.

© 1990 Optical Society of America