High-Speed Nonreciprocal Optical Switching Using Phase Shift Induced by Magnetostatic Surface Waves

Interaction between optical guided waves and magnetostatic waves (MSW) has great potential for wideband optical signal processing directly at microwave signal frequencies. However, till now, all theoretical and experimental investigation has focused on optical mode conversion involving a change in polarization induced by magnetostatic waves. So far, the efficiency of this mode conversion has been low. Here, we propose and analyze, for the first time, the feasibility of obtaining an optical phase shift induced by magnetostatic surface waves in thin film waveguides. We show that with proper selection of the waveguide parameters, it is possible to obtain a phase shift which is sufficient for design of efficient optical-MSW signal processing devices. Further, we propose and analyze a device structure for an optical switch based upon this phase shift and demonstrate the design feasibilty through a numerical example.