The nonreciprocal effect is the difference Δβ = β<sub>forward</sub> − β<sub>backward</sub> between forward and backward-propagation constants of optical modes. This effect is analyzed for the fundamental TM<sub>00</sub> mode of channel waveguides in epitaxially grown magnetic garnet films. To increase ‖Δβ‖, double layers with opposite signs of Faraday rotation are used to prepare the waveguides. It is shown that the temperature dependence of Δβ 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, ‖Δβ‖ is decreased by ~35% at 295 K.
© 1999 Optical Society of America
(130.3130) Integrated optics : Integrated optics materials
(160.3820) Materials : Magneto-optical materials
(230.3240) Optical devices : Isolators
(230.3810) Optical devices : Magneto-optic systems
(230.7380) Optical devices : Waveguides, channeled
Norbert Bahlmann, Michael Wallenhorst, Ludger Wilkens, Volker Backherms, Andree Josef, Peter Hertel, and Horst Dötsch, "Reduction of the Temperature Dependence of the Nonreciprocal Effect of Magneto-Optic Channel Waveguides," Appl. Opt. 38, 5747-5751 (1999)