Abstract
Ce-, Co-, and (Ce,Co)-doped Sr
0.61Ba
0.39Nb
2O
6 (SBN:61) crystals with different concentrations were grown by Czochralski technique in the congruent composition. It is the first report of double-doped SBN crystals with Ce and Co. The doping ions Ce and Co occupy 15- (or 12-) fold coordinated and 6-fold coordinated lattice sites in crystal, respectively. A little change of the lattice constants induced by doping ions were detected by XRD experiments. Absorption spectra show that Ce
3+ and Co
3+ are dominant valence status in SBN:61 crystal. Ce and Co doping enhances two-beam coupling gain coefficient and photorefractive response speed, due to these doping ions donating or capturing electrons during the photorefractive process.