With previous NSF support, we have begun a careful study of mode conversion between optical guided modes in magnetic garnet thin films induced by microwave magnetostatic waves. This interaction may lead to new microwave and optical signal processing devices including microwave spectrum analyzers and optical frequency shifters. We propose to continue this work by studying two issues related to increasing the conversion efficiency resulting from the interaction. First, the microwave nonlinear phenomena which occur when high microwave power is used to achieve efficient mode conversion will be studied by not only examining the microwave spectrum, but by examining the optical spectrum of the converted mode and the angular distribution of the diffracted beam. Second, we propose to study optical mode conversion induced by magnetostatic waves propagating in a separate layer of a garnet heterostructre. Previous theoretical studies have suggested that efficient mode conversion may be easier to obtain in a heterostructre, with separate layers optimized for microwave and optical properties, than in a single magnetic layer.
