EFFECTS OF HEAT-TREATMENT WITH QUENCHING ON PHOTOREFRACTIVE PROPERTIES OF CERIUM-DOPED AND EUROPIUM-DOPED STRONTIUM BARIUM NIOBATE

The heat treatment of Ce, Eu-doped Sr0.61Ba0.39Nb2O6-delta (SBN) singl e crystals in an oxygen atmosphere, whereby samples are quenched after annealing to prevent any reaction during cooling, is discussed. We we re able to obtain fairly good reproducibility with the quenching metho d. Photorefractive trap densities changed drastically as a result of t he treatment, whereas absorption did not change significantly, and thi s is beneficial for volume multiplexing. For long-term data storage, w e found that a lower annealing temperature was better. We discuss the effects of the treatment on the photorefractive properties of SBN in r elation to oxygen vacancies. (C) 1998 Optical Society of America.