Quantized spin waves and perpendicular standing spin waves stimulated by current in a single-layered ferromagnetic wire

TL;DR

This paper investigates how RF and DC currents stimulate quantized and standing spin waves in a ferromagnetic wire, revealing new spin wave modes and their dependence on current and magnetic field, with a phenomenological model explaining the observations.

Contribution

It introduces a phenomenological model for current-induced spin wave excitation and demonstrates the stimulation of quantized and standing spin waves in a single-layered ferromagnetic wire.

Findings

Detection of additional spin wave mode via rectification

Correlation between model and experimental results

Dependence of spin dynamics on currents and magnetic field

Abstract

The rectifying effect of radio-frequency (RF) current is highly sensitive in terms of the spatial spin distribution and dynamics. It emerged that an additional spin wave mode was stimulated by the direct-current (DC) current and that this spin wave was detectable via rectification of the RF current. A phenomenological model to describe the time-dependent anisotropic magnetoresistance or time-dependent planer Hall effect is proposed and found to correlate well to the experimental results. The nonlinear spin dynamics accompanying additional spin waves are studied as functions of the RF and DC currents, the external magnetic field, and the applied field direction.