Abstract

The band model¹⁾ is commonly used to describe photorefractive effects, assuming that optically excited carriers (electrons or holes), from band gap impurities levels, migrate to the dark regions of the crystal where they are trapped. If iron has been put forward to give predominant photorefractive species in BaTiO₃, either in intentionally doped²⁾ or in as said pure crystals³⁾, others 3d transitions elements could play a part in these mechanisms, as they tend also to behave as deep centers, and can significantly affect the electronic properties of the material involved.

© 1987 Optical Society of America