Strong and tunable magnetoelectric coupling in 2D trilayer heterostructures

TL;DR

This paper predicts that 2D ferroelectric and polar magnetic metal heterostructures can exhibit strong, tunable magnetoelectric coupling, enabling electric control of skyrmions for spintronics applications, based on density functional theory calculations.

Contribution

It introduces a novel theoretical design of 2D heterostructures with strong magnetoelectric coupling and electric control of skyrmions, expanding possibilities for spintronics.

Findings

Density functional theory confirms effective magnetoelectric coupling in proposed heterostructures.

Multiple polarization states enable electric-field control of skyrmions.

Strong Dzyaloshinskii-Moriya interactions facilitate skyrmion generation.

Abstract

The quest for electric-field control of nanoscale magnetic states such as skyrmions, which would impact the field of spintronics, has led to a challenging search for multiferroic materials or structures with strong magnetoelectric coupling and efficient electric-field control. Here we report a theoretical prediction that such phenomena can be realized in two-dimensional (2D) bilayer FE/PMM and trilayer FE/PMM/FE heterostructures (two-terminal and three-terminal devices), where FE is a 2D ferroelectric and PMM is a polar magnetic metal with strong spin-orbit coupling. Such a PMM has strong Dzyaloshinskii-Moriya interactions (DMI) that can generate skyrmions, while the FE can generate strong magnetoelectric coupling through polarization-polarization interactions. In trilayer heterostructures, contact to the metallic PMM layer enables multiple polarization configurations for electric-field control of skyrmions. We report density-functional-theory calculations for particular material choices that demonstrate the effectiveness of these arrangements, with the key driver being the polarization-polarization interactions between the PMM and FE layers. The present findings provide a method to achieve strong magnetoelectric coupling in the 2D limit and a new perspective for the design of related spintronics.