Spectral shape deformation in inverse spin Hall voltage in YFeOPt bilayers at high microwave power levels

強マイクロ波領域でのYFeOPt2層膜における逆スピンHallスペクトルの形状変形

Lustikova, J.*; 塩見 雄毅*; 半田 優*; 齊藤 英治

Lustikova, J.*; Shiomi, Yuki*; Handa, Yu*; Saito, Eiji

We report on the deformation of microwave absorption spectra and of the inverse spin Hall voltage signals in thin film bilayers of yttrium iron garnet (YIG) and platinum at high microwave power levels in a 9.45 GHz TE cavity. As the microwave power increases from 0.15 to 200 mW, the resonance field shifts to higher values, and the initially Lorentzian spectra of the microwave absorption intensity as well as the inverse spin Hall voltage signals become asymmetric. The contributions from opening of the magnetization precession cone and heating of YIG cannot well reproduce the data. Control measurements of inverse spin Hall voltages on thin-film YIGPt systems with a range of line widths underscore the role of spin-wave excitations in spectral deformation.