Topological magnetic dipolar interaction and non-local electric magnetization control in topological insulator heterostructures

TL;DR

This paper theoretically demonstrates a topological magnetic dipole-dipole interaction in topological insulator heterostructures, enabling non-local control of magnetization through long-range Coulomb interactions between separated interfaces.

Contribution

It introduces a novel topological magnetic dipole interaction mechanism and shows how it can be used for non-local magnetic texture control in heterostructures.

Findings

Topological magnetic dipole-dipole interaction arises from Coulomb interactions.

Long-range coupling enables non-local magnetic texture formation.

Analytical magnetization dynamics derived for heterostructure interfaces.

Abstract

The magnetoelectric effect predicted in topological insulators makes heterostructures that combine magnetic materials and such insulators promising candidates for spintronics applications. Here, we theoretically consider a setup that exhibits two well-separated interfaces between a topological insulator and a ferromagnetic insulator. We show that there is a topological magnetic dipole-dipole interaction stemming from long-range Coulomb interactions. We analytically derive the magnetization dynamics at the two interfaces and discuss how the long-range coupling can be applied to non-locally induce the formation of a magnetic texture at one interface by suitably gating the other interface.