Magnetoelectric torque in polar magnetic bilayers

TL;DR

This paper introduces a magnetoelectric torque mechanism in polar magnetic bilayers that enables ultra-fast, energy-efficient switching of magnetization using an electric field, bypassing traditional spin-orbit methods.

Contribution

It proposes a novel magnetoelectric torque mechanism for magnetization switching in polar magnetic bilayers, demonstrated through first-principles calculations and simulations.

Findings

Magnetoelectric torque can flip spins within a few picoseconds.

The mechanism does not rely on spin-orbit coupling.

It is effective in polar magnetic homostructures and heterostructures.

Abstract

Energy-efficient fast switching of spin orientations or textures is a core issue of spintronics, which is highly demanded but remains challenging. Different from the mainstream routes based on spin-transfer torque or spin-orbit torque, here we propose another mechanism coined as magnetoelectric torque to switch the magnetization in polar magnetic bilayers via pure electric field. In some magnetic van der Waals bilayers, when the electrostatic energy of polarization can compensate the interlayer magnetic coupling, a magnetoelectric torque is generated to fastly flip spins within a few picoseconds, which is demonstrated by combining the first-principles calculations, analytic model, as well as atomistic simulations. Such a magnetoelectric torque doesn't rely on the spin-orbit coupling and is generally active in polar magnetic homostructures and heterostructures. Our work provides an alternative route to switch magnetization in nanoscale, which may benefit the energy-saving and fast-response spintronic devices.