Electrical detection of parallel parametric amplification and attenuation in $\mathrm{Y}_3\mathrm{Fe}_5\mathrm{O}_{12}$/$\mathrm{Pt}$ bilayer disk

TL;DR

This paper demonstrates phase-dependent parametric amplification and attenuation of magnetization dynamics in a YIG/Pt bilayer disk, with a maximum gain of 11.4 dB, using a systematic experimental and theoretical approach.

Contribution

It provides the first quantitative analysis of phase-dependent parametric amplification in YIG/Pt disks, including a theoretical model and optimal condition identification.

Findings

Phase-dependent amplification and attenuation occur every π/2 phase shift.

Maximum gain achieved is 11.4 dB.

Gain depends on pump power and magnetic field conditions.

Abstract

We report a systematic quantitative evaluation of parametric amplification gain of magnetization dynamics in ytirrium iron garnet ($\mathrm{Y}_3\mathrm{Fe}_5\mathrm{O}_{12}$) thin disk via a.c. spin pumping and inverse spin Hall effect. We demonstrate its signature phase-dependence where amplification and attenuation occur every $\frac{\pi}{2}$ 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 the amplification is investigated by measuring the magnetic field dependence, where we find the highest gain of 11.4 dB.