Spin-Wave Anisotropy Effects in Parallel Pumping in YIG

Abstract

A second ``corner'' has been observed on the ``butterfly curve'' of the parallel pumping experiment on YIG (yttrium iron garnet) at x‐band frequency. The extra corner occurs in all crystallographic directions in a (110) plane except the [100] and [111]. The separation between the two corners closely equals the anisotropy‐produced azimuthal angle splitting of the top of the spin‐wave band. This splitting occurs in cubic YIG in all directions except the [100] and [111]. The shape of the butterfly curve in the region between the corners is partially explained by the variation in spin‐wave ellipticity with azimuthal angle. A variation in spin‐wave linewidth for k→0 with azimuthal angle may be responsible for the remaining discrepancy.