Magnetization switching by microwaves synchronized in the vicinity of precession frequency

TL;DR

This paper presents a theoretical framework for magnetization switching driven solely by microwaves, where the microwave frequency is close to but slightly different from the magnetization's precession frequency, enabling energy absorption and switching.

Contribution

The paper introduces a new theoretical model describing microwave-induced magnetization switching near precession frequency, with analytical conditions for switching validated by numerical simulations.

Findings

Derived analytical condition for switching based on frequency difference parameter

Confirmed theoretical predictions with numerical simulation results

Identified the role of energy absorption in microwave-driven switching

Abstract

We propose a theoretical framework of a magnetization switching induced solely by a microwave. The microwave frequency is always close to but slightly different from the oscillation frequency of the magnetization. By efficiently absorbing energy from the microwave, the magnetization climbs up the energy landscape to synchronize the precession with the microwave. We introduced a dimensionless parameter $\epsilon$ determining the difference between the microwave frequency and the instant oscillation frequency of the magnetization. We analytically derived the condition of $\epsilon$ to switch the magnetization, and confirmed its validity by the comparison with numerical simulations.