Combined EPR/optical investigations of light-induced charge transfers in photorefractive materials

摘要

A way to elucidate the light-induced charge transfer processes, which lead to refractive index changes in phtore- fractive materials, is outlined. Using this method, the electron paramagnetic resonance (EPR) information on the chemical identity and structure of defects, between which the transfers occur, is correlated to the corresponding optical absorption bands. On the basis of these bands alone charge transfer phenomena can then be analyzed. The determi- nation of special charge transfer features is illustrated with examples on defects in BaTiO_3.