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

Abstract A way to elucidate the light-induced charge transfer processes, which lead to refractive index changes in photorefractive 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 determination of special charge transfer features is illustrated with examples on defects in BaTiO3.