Optimal Control of Stochastic Magnetization Dynamics by Spin Current

TL;DR

This paper introduces an optimal control method for stochastic magnetization dynamics driven by spin currents, aiming to manipulate the probability of rare magnetic events in recording technologies.

Contribution

It develops a novel approach to control fluctuation-induced magnetization switching by minimizing the Freidlin-Wentzell action functional, enhancing magnetic recording techniques.

Findings

Optimal control reduces the probability of undesired switching.

Demonstrates improved reliability in thermal-driven magnetization switching.

Provides a framework for controlling stochastic magnetic phenomena.

Abstract

Fluctuation-induced stochastic magnetization dynamics plays an important role in magnetic recording and writing. Here we propose that the magnetization dynamics can be optimally controlled by the spin current to minimize or maximize the Freidlin-Wentzell action functional of the system hence to increase or decrease the happening probability of the rare event. We apply this method to study thermal-driven magnetization switching problem and to demonstrate the advantage of the optimal control strategy.