Theory of the Strain-Induced Magnetoelectric Effect in Planar Dirac Systems

TL;DR

This paper analyzes how strain induces a magnetoelectric effect in 2D Dirac systems, linking it to Berry curvature and orbital magnetic moments, enabling local charge control via magnetic fields.

Contribution

It introduces a theoretical framework connecting strain-induced magnetoelectric response to Berry curvature and orbital magnetic moments in 2D Dirac materials.

Findings

Magnetoelectric response relates to Berry curvature and orbital magnetic moments.

Strain can locally induce and control charge densities.

The effect parallels piezoelectric responses in similar materials.

Abstract

The magnetoelectric response in inversion-breaking two dimensional Dirac systems induced by strain is analyzed. It is shown that, in the same way that the piezoelectric response in these materials is related to the valley Chern number, the strain-induced magnetoelectric effect is related both to the non trivial Berry curvature and the derivative of the orbital magnetic moment per valley. This phenomenon allows to locally induce and control charge densities by an external magnetic field in strained zones of the sample.