Photoinduced helical metal and magnetization in two-dimensional electron systems with spin-orbit coupling

TL;DR

This paper proposes a method to induce helical metals and magnetization in 2D semiconductors using THz light, enabling control over their electronic and magnetic properties for potential spintronics applications.

Contribution

It introduces a novel approach to realize helical metals via light application on common semiconductors, expanding the scope of materials and control methods.

Findings

Circularly polarized light enables magnetization manipulation.

The system exhibits large anomalous Hall conductivity.

Light-induced effects suggest new material engineering possibilities.

Abstract

Helical metals realized at the surfaces of topological insulators have recently attracted wide attention due to their potential applications in spintronics. In this paper we propose to realize helical metals through the application of THz light on common two-dimensional semiconductors and discuss their observable properties. We show that the application of circularly polarized light enables coherent manipulation of magnetization. Moreover, for a range of chemical potentials the system behaves as a helical metal, exhibiting a large anomalous Hall conductivity and associated magnetoelectric effect. Proposed dynamical engineering of material properties through light in much-studied materials opens new perspectives for future applications.