Brillouin scattering from parallel pump instabilities in YIG (abstract)

Brillouin light scattering has been observed from parametrically excited magnons by parallel pumping in a 4‐μ yttrium iron garnet film at 9.4 GHz. Scattering from the spin‐waves could be observed continuously from the thermal level through the nonlinear region of parametrically excited magnons. Magnons with small wave vectors propagating perpendicular to the static field are seen to have the lowest critical field as predicted theoretically. The spectra of these parametric excitations show a pronounced structure.