Enhanced magnetoelectric coupling in two-dimensional hybrid multiferroic heterostructures

TL;DR

This study predicts enhanced magnetoelectric coupling in a hybrid 2D multiferroic heterostructure of CrCl3 and CuCrP2S6 using first-principles calculations, highlighting its potential for advanced multifunctional devices.

Contribution

It introduces a novel hybrid multiferroic heterostructure with robust, enhanced magnetoelectric coupling and elucidates the underlying interfacial effects driving this enhancement.

Findings

Interlayer magnetic configuration switches with electric polarization.

Magnetoelectric coupling remains robust in multilayer structures.

Interfacial effects like spin local-field and proximity polarization are key.

Abstract

Magnetoelectric coupling in insulating multiferroic materials is invaluable for both fundamental research and multifunctional device applications. However, material realization remains a significant challenge. We employ first-principles calculations to predict an enhanced and stacking-robust magnetoelectric coupling in a multiferroic van der Waals heterostructure consisting of CrCl3 and CuCrP2S6. Within this heterostructure, the intralayer ferroic orders exhibit characteristics of a type-I multiferroic, while the interlayer ferroic orders resemble those of a type-II multiferroic, thus creating a hybrid-type multiferroic. Notably, the interlayer magnetic configuration can be switched upon electric polarization reversal, while maintaining the insulating property without any nontrivial phase transitions. Our analysis reveals a strongly interfacial spin local-field effect and proximity polarization effect on band alignments. These factors work synergistically to decide the interlayer exchange interaction and drive enhanced magnetoelectric coupling. Finally, we show that this magnetoelectric effect is robust in multi-layer structures, exhibiting a dependence on the layer number's parity. This research offers promising prospects for discovering enhanced magnetoelectric couplings in hybrid multiferroic van der Waals heterostructures.