Design of semiconductor-waveguide-type optical isolators using the nonreciprocal loss/gain in the magneto-optical waveguides having MnAs nanoclusters

We have theoretically analyzed semiconductor-waveguide-type optical isolators, which are based on the nonreciprocal loss/gain in the magneto-optical waveguide having MnAs nanoclusters embedded in an InAlAs matrix. The whole device structure is grown on an InP substrate and the operation wavelength is 1.55 mum. In the TM mode, more than 119 dB/cm of isolation is predicted and the optimum device structure is discussed. Furthermore, we proposed and theoretically analyzed a semiconductor-waveguide-type optical isolator for the TE mode, which can realize 36 dB/cm of isolation. Since out waveguide-type optical isolators are composed of ail semiconductor-based materials, they can be easily integrated with III-V based optoelectronic devices such as edge-emitting laser diodes. (C) 2002 American Institute of Physics.