# Electrically driven spin torque and dynamical Dzyaloshinskii-Moriya interaction in magnetic bilayer systems

## TL;DR

This paper proposes a theoretical method to control magnetism in bilayer systems using electric voltages and Rashba spin-orbit interaction, enabling energy-efficient manipulation of magnetic states without Joule heating.

## Contribution

It introduces a novel voltage-driven spin torque mechanism that mimics current-induced effects but avoids energy losses, and reveals its role as an interfacial Dzyaloshinskii-Moriya interaction.

## Key findings

- Voltage-induced spin torques can manipulate magnetism without Joule heating.
- The torques act as an interfacial Dzyaloshinskii-Moriya interaction.
- Potential to create noncollinear magnetic structures like skyrmions.

## Abstract

Efficient control of magnetism with electric means is a central issue of current spintronics research, which opens an opportunity to design integrated spintronic devices. However, recent well-studied methods are mostly based on electric-current injection, and they are inevitably accompanied by considerable energy losses through Joule heating. Here we theoretically propose a way to exert spin torques into magnetic bilayer systems by application of electric voltages through taking advantage of the Rashba spin-orbit interaction. The torques resemble the well-known electric-current-induced torques, providing similar controllability of magnetism but without Joule-heating energy losses. The torques also turn out to work as an interfacial Dzyaloshinskii-Moriya interaction which enables us to activate and create noncollinear magnetism like skyrmions by electric-voltage application. Our proposal offers an efficient technique to manipulate magnetizations in spintronics devices without Joule-heating energy losses.