Spin-wave diagnostics of the magnetization distribution over the thickness of a ferrite film

Abstract

High-intensity microwave excitation of short-wavelength exchange spin waves in a normally magnetized epitaxial film of an yttrium iron garnet (YIG) has been found. The waves were excited in a thin diffusion layer at the boundary between the YIG film and a nonmagnetic gadolinium gallium garnet substrate. It propagates into the YIG film. In the pulsed excitation mode, a series of delayed echo pulses of the exchange waves reflected from the opposite surface of the film was observed. The distribution function of the magnetization over the thickness of the ferrite film was calculated based on the measurements of the time delay of the echo pulses. The dispersion characteristics of the detected waves were calculated.