Magneto-optical properties of Y/sub 3-x-y/Ce/sub x/La/sub y/Fe/sub 5/O/sub 12/

Yttrium iron garnet YIG has been characterized extensively for its use in magneto-optic devices, such as optical isolators and magnetic field sensors. The effects of doping cerium and lanthanum into the YIG host are reported. In optical isolator applications operating at 1.31 /spl mu/m and 1.54 /spl mu/m, where miniaturization and temperature stability are important, cerium and lanthanum-containing compositions are considered as alternatives to pure YIG. Measurements were made of the Faraday rotation as a function of temperature, extinction ratio, and saturation magnetization in several garnet compositions. Improvement of optical transmission at 1.31 /spl mu/m and 1.54 /spl mu/m was achieved by the incorporation of small amounts of calcium.