Electrical detection of parallel parametric amplification and attenuation in a Y3Fe5O12/Pt bilayer disk

We report a systematic quantitative evaluation of parametric amplification gain of magnetization dynamics in an yttrium iron garnet (Y3Fe5O12) thin disk via ac spin pumping and the inverse spin Hall effect. We demonstrate its signature phase dependence where amplification and attenuation occur every i phase shift of the input signal. The results also show the pump-power dependence of the gain that is explained well by our theoretical model. Finally, the optimal conditions for amplification are investigated by measuring the magnetic field dependence, where we find the highest gain of 11.4 dB.