Comparative analysis of electro-optic properties in bismuth silicate grown by the Czochralski, Bridgman–Stockbarger, and hydrothermal techniques

Abstract The relationship between growth conditions and electro-optic properties was investigated in a comparative analysis of BSO grown by the Czochralski, Bridgman–Stockbarger, and hydrothermal methods. Hydrothermal material was confirmed to be near intrinsic. Due to a higher defect concentration, Czochralski material exhibited higher absorption and photoconductivity near the band-edge as well as a stronger photochromic response than the Bridgman material. No photochromic response was observed in samples that were grown in a sealed ampoule. Subsequent experiments revealed that high temperature annealing in the presence of a limited oxygen supply removed the photochromic response in BSO. Photoconductivity and photorefractivity measurements showed fundamental changes in carrier lifetime as a result of high temperature annealing in a reduced oxygen atmosphere. Growth and processing conditions were seen to have a significant effect on defect incorporation and the resultant electro-optical properties in BSO.