Abstract
Doped with transition metal and/or rare earth ions, strontium barium niobate (SBN) crystals have received considerable attention due to their attractive photorefractive properties. in this paper, undoped and four Go-doped SBN crystals of various concentrations were grown by Czochralski method. Transmission spectra show that the Co ions in the crystals cause a strong board absorption band resulted in charge-transfer transition, and some other absorption peaks associated with d-d transition.