OPTICAL-PROPERTIES OF BISMUTH AND GALLIUM SUBSTITUTED THULIUM IRON-GARNET FILMS

Bismuth and gallium substituted films of thulium iron garnet, grown by liquid phase epitaxy on [111] oriented substrates of gadolinium galli um garnet, are investigated for optical isolator applications. At a wa velength of lambda = 1.3 mum the optical damping, the refractive index , the optical anisotropy, and the Faraday rotation are measured as fun ction of the substitution level. It turns out that the growth induced optical anisotropy is very small, similar to the magnetic anisotropy. The observed difference between forward and backward propagation const ants of TM modes is in excellent agreement with calculations.