Low-energy magnetoelectric control of domain states in exchange-coupled heterostructures

TL;DR

This paper demonstrates a method to control magnetic domain switching in magnetoelectric heterostructures by balancing exchange coupling and Zeeman energies, enabling electric manipulation at low energy costs.

Contribution

It introduces a novel approach to overcome energy barriers in antiferromagnetic switching by compensating exchange coupling with Zeeman energy, verified through experiments and modeling.

Findings

Controlled magnetic domain switching at zero-threshold electric field.

Tunable switching conditions via magnetic and electric fields.

Demonstrated switching at a magnetic field of 2.6 kOe.

Abstract

The electric manipulation of antiferromagnets has become an area of great interest recently for zero-stray-field spintronic devices, and for their rich spin dynamics. Generally, the application of antiferromagnetic media for information memories and storage requires a heterostructure with a ferromagnetic layer for readout through the exchange-bias field. In magnetoelectric and multiferroic antiferromagnets, the exchange coupling exerts an additional impediment (energy barrier) to magnetization reversal by the applied magnetoelectric energy. We proposed and verified a method to overcome this barrier. We controlled the energy required for switching the magnetic domains in magnetoelectric \cro films by compensating the exchange-coupling energy from the ferromagnetic layer with the Zeeman energy of a small volumetric spontaneous magnetization found for the sputtered \cro films. Based on a simplified phenomenological model of the field-cooling process, the magnetic and electric fields required for switching could be tuned. As an example, the switching of antiferromagnetic domains around a zero-threshold electric field was demonstrated at a magnetic field of 2.6 kOe.