Reduction of the temperature dependence of the nonreciprocal effect of magneto-optic channel waveguides

Abstract

The nonreciprocal effect is the difference Delta beta= P-forward - beta(backward) between forward and backward-propagation constants of optical modes. This effect is analyzed for the fundamental TM00 mode of channel waveguides in epitaxially grown magnetic garnet films. To increase Delta beta, double layers with opposite signs of Faraday rotation are used to prepare the waveguides. It is shown that the temperature dependence of Delta beta can be reduced considerably if the layer with positive Faraday rotation, which is at room temperature close to the Curie point, is replaced by a paramagnetic layer with negligible Faraday rotation. Concurrently, however, Delta beta is decreased by similar to 35% at 295 K. (C) 1999 Optical Society of America OCIS codes: 130.3130, 160.3820, 230.3240, 230.7380, 230.3810.