Photoinduced Chern insulating states in semi-Dirac materials

TL;DR

This paper demonstrates that circularly polarized light can induce topological Chern insulating states in 2D semi-Dirac materials, enabling control over their topological phases through light intensity and polarization.

Contribution

It reveals how electromagnetic fields can induce and control topological phase transitions in semi-Dirac materials, a novel mechanism for topological state engineering.

Findings

Circularly polarized light induces Chern insulating states.

Topological transitions depend on light polarization.

Control over topological phases via light parameters.

Abstract

Two-dimensional (2D) semi-Dirac materials are characterized by a quadratic dispersion in one direction and a linear dispersion along the orthogonal direction. We study the topological phase transition in such 2D systems in the presence of an electromagnetic field. We show that a Chern insulating state emerges in a semi-Dirac system with two gapless Dirac nodes in the presence of light. In particular, we show that the intensity of a circularly polarized light can be used as a knob to generate topological states with nonzero Chern number. In addition, for fixed intensity and frequency of the light, a semi-Dirac system with two gapped Dirac nodes with trivial band topology can reveal the topological transition as a function of polarization of the light.