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Spin-Acoustic Wave Interaction in Time- and Spatially-Varying Magnetic Fields.
STANFORD UNIV CA MICROWAVE LAB
Pagination or Media Count:
Theoretical and experimental investigations were conducted on the propagation of elastic, magnetoelastic, and spin waves in the presence of time-varying and time- and spatially-varying magnetic fields. The propagating media are axially biased rods of yttrium iron garnet YIG, Ga substituted GaYIG, Mn substituted YIG MnYIG, and non-magnetic yttrium aluminum garnet YAG, all much larger than the propagation wave length so that a uniform plane wave solution description is possible. The theoretical calculations and experimental results verify that a magnetoelastic wave propagating in a time-varying magnetic field experiences a change in frequency energy at constant wavenumber momentum while the same wave propagating in a spatially-varying magnetic field experiences a change in wavenumber momentum at constant frequency energy. A time- and spatially-varying field yields changes in both frequency and wavenumber and results in frequency and wavenumber sweeping. The use of both time-varying and spatially-varying magnetic fields provides a number of new signal processing effects. Author
APPROVED FOR PUBLIC RELEASE