Ce-substituted yttrium iron garnet films prepared on Gd3Sc2Ga3O12 garnet substrates by sputter epitaxy

Ce-substituted yttrium iron garnet films are epitaxially grown in situ on (111)-oriented substrates of Gd3Sc2Ga3O12 garnet by conventional rf diode sputtering for application to magneto-optic waveguide devices in optical communication systems. The lattice constant of the substrates is larger than that of the previously used (Gd,Ca)(3)(Ga,Mg,Zr)(5)O-12 garnet substrates whose lattice constant is smaller than that of the films. The lowest ever reported propagation losses of 9.7 dB/cm in the TE mode and 5.8 dB/cm in the TM mode are obtained for a film thickness of 0.5 mu m at lambda = 1.55 mu m. (C) 1997 American Institute of Physics.