Non-linear dynamics near exceptional points of synthetic antiferromagnetic spin-torque oscillators

TL;DR

This paper investigates the non-linear dynamics of a synthetic antiferromagnetic spin-torque oscillator near exceptional points, revealing sensitive power dependence useful for sensor applications.

Contribution

It provides an analytical and numerical analysis of the non-linear behavior and phase diagram of the system, highlighting the effects of exceptional points.

Findings

Power sensitivity peaks near exceptional points

Analytical and numerical phase diagrams constructed

Potential applications in sensitive magnetometry

Abstract

We consider a synthetic antiferromagnetic spin-torque oscillator with anisotropic interlayer exchange coupling. This system exhibits exceptional points in its linearized dynamics. We find the non-linear dynamics and the dynamical phase diagram of the system both analytically and numerically. Moreover, we show that, near one of the exceptional points, the power of the oscillator depends extremely sensitively on the injected spin current. Our findings may be useful for designing sensitive magnetometers and for other applications of spin-torque oscillators.