Theory for magnetostatic forward volume wave excitation

The present paper reports a theory for the excitation of magnetostatic forward volume waves (MSFVW’s) in YIG films by the most basic of all transducers, viz., an electric line current source, and various ramifications thereof (microstrip, meander-line and grating couplers). Expressions for power in the MSFVW’s excited by these transducers are derived, and computations of the transducer excitation characteristics are presented. It is found that all transducers yield a significant excitation of higher-order MSFVW’s, with the best suppression of these modes provided by the single microstrip coupler.