Magneto-Opticial Properties of Bi-Substituted GdIG Films Grown by LPE

Reduction of optical absorption as the amount of Bi in Bi-substituted films is increased is discussed. The amount of Bi in the films grown was controlled by adjusting the supercooling temperature of the solvent, the ratio of PbO to Bi₂O₃ in the solvent, the substrate rotation speed and other parameters. Variation in Bi content with respect to Bi-YIG was found at substrate rotation speeds of 84 rpm and 170 rpm. The measurements of the absorption characteristics of Bi-GdIG and Bi-GdGaIG films grown on a GGG substrate indicated that they included a Bi quantity of approximately 0.8 with respect to the Bi-GdIG. A figure of merit of 6.7 deg/dB was obtained for a 21.2 μm thick Bi-GdIG film at a wavelength of 0.76 μm.