Bright photorefractive spatial solitons in barium - calcium titanate crystals

摘要

We report the experimental investigation both, of the one - dimensional and two - dimensional bright screening spatial solitons in a promising photorefractive crystal of barium - calcium titanate doped with iron. The effects of the partial trapping of the spatially incoherent ordinarily polarized background light within the soliton - induced planar waveguide as well as the regular oscilations of the light beam intensity and width during the beam self- focusing are observed. For the crystal sample, doped with higher dose of iron (290 ppm), we also find the self - defocusing of light beams due to the light - induced negative photovoltaic lens in the absence of the externally applied electric field.