Spin-wave diffraction in a homogeneous ferromagnetic layer

The authors report theoretical and experimental research on diffraction effects associated with the excitation and propagation of surface spin waves. Expressions are derived for the Green's matrix of a point source of surface spin waves in the far-field region, and a simple scalar form of notation for the Green's function of a point source in an anisotropic medium is proposed. This form can be used to calculate the far diffraction field of an arbitrary planar antenna. The Green's functions obtained for the point source are used to calculate the radiation patterns of linear microstrip transducers, as well as the fraction of energy picked up by an analogous transducer positioned opposite the radiating transducer in the far-field region. The computational method is used to reduce the error in local monitoring of the quality of yttrium-iron garnet (YIG) films by the double-measurement method. The authors present the results of an experimental study of the dispersion characteristics of surface spin waves for different angles between andH_i, as well as a theoretical and experimental study of transducers that focus surface spin waves.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 32–48, April, 1989.The authors would like to thank S. G. Suchkov and Yu. A. Zyuryukin for valuable comments during a discussion of the results.