Floquet dynamics in multi-Weyl semimetals

TL;DR

This paper investigates how periodic circularly polarized light can induce phase transitions in multi-Weyl semimetals from trivial insulators to Weyl semimetals, revealing tunable topological properties and measurable transport signatures.

Contribution

It introduces a method to dynamically induce and control Weyl semimetal phases in multi-Weyl systems using Floquet engineering with circularly polarized light.

Findings

Phase transition from trivial insulator to Weyl semimetal under light irradiation.

Large anomalous Hall conductivity in the driven phase.

Potential experimental detection via transport and pump-probe spectroscopy.

Abstract

Multi-Weyl semimetals(m-WSMS) are characterized by anisotropic non-linear energy dispersion along 2-D plane and a linear dispersion in orthogonal direction. They have topological charge J and are realized when two or multiple Weyl nodes with nonzero net monopole charge bring together onto a high-symmetry point. The model Hamiltonians of such systems show various phases such as trivial normal insulators (NIs), WSMs and quantum anomalous Hall(QAH) states depending on the model parameters. We study a periodic driving of such Hamiltonians in trivial NI phase by circularly polarized light and shows this phase can be tunable to Weyl semimetals phase. This transition can be accomplished with large anomalous Hall conductivity which could be observed in transport measurements or pump-probe angle resolved photoemission spectroscopy experiments.