Light-Induced Absorption in Photorefractive Barium Titanate Doped with Rhodium

The light-induced absorption of barium titanate doped with rhodium (BaTiO₃:Rh) is characterized in near-infrared spectral region. It decreases with the wavelength of the probe beam from 700 to 840 nm, and is significantly dependent on the polarization of the probe beam and insensitive to the polarization of the pump beam. The light-induced absorption as high as 0.32 cm^-1 is obtained for ordinary-polarized probe beam at λ =730 nm. The observations are interpreted by the photorefractive two-center or one center with three valence states model.