Excitation of gigahertz magnetoelastic waves in terbium films: Field dependence

Transverse magnetoelastic excitations in polycrystalline terbium films have been observed using pulse-echo spectrometers with a dc magnetic field applied normal to the film, and an rf field applied in the film plane. A coupled magnetoelastic model analysis, with one adjustable parameter, correctly predicts the observed signal intensity, field dependence, mode, and frequency. Since the magnon energy gap lies well above the operating frequencies, the observed signals result from the magnetic excitation of ''phononlike'' normal modes