A single-crystalline double-layered structure of a pure (80-µm)/doped (39-µm)/pure Bi12SiO20 (BSO) substrate was grown for the first time by a new liquid-phase epitaxial growth to form an optical waveguide. The waveguide layer is BSO doped with CaCO3 (0.1 wt. %) and Ga2O3 (0.197 wt. %) and has a refractive index 0.07% higher than the substrate. The optical absorption coefficients were decreased by more than 1 order of magnitude by doping with the elements Ca and Ga. The high-sensitive photoconductivity of pure BSO was also reduced. Using these unique properties, we have constructed a new type of optically controlled planar optical switch.
© 1982 Optical Society of America
Kohji Tada, Yoshiki Kuhara, Masami Tatsumi, and Takeshi Yamaguchi, "Liquid-phase epitaxial growth of bismuth silicon oxide single-crystal film: a new optically activated optical switch," Appl. Opt. 21, 2953-2959 (1982)