Weyl nodes with higher-order topology in an optically driven nodal-line semimetal

TL;DR

This paper demonstrates how circularly polarized light can induce and control Weyl semimetal states with higher-order topology in a driven nodal-line semimetal, enabling tunable topological surface and hinge states.

Contribution

It introduces a method to generate and manipulate Floquet Weyl states with higher-order topology using optical driving in a nodal-line semimetal.

Findings

Floquet Weyl semimetal states can be induced by circularly polarized light.

Weyl node locations and Fermi arc curvature are tunable via light direction and angle.

Higher-order topological states support both hinge and surface Fermi arcs.

Abstract

Creating and manipulating topological states is a key goal of condensed matter physics. Periodic driving offers a powerful method to manipulate electronic states, and even to create topological states in solids. Here, we investigate the tunable Floquet states in a periodically driven higher-order nodal line semimetal with both spatial inversion and time-reversal symmetries. We found that the Floquet Weyl semimetal states, which support both one-dimensional hinge Fermi arc and two-dimensional surface Fermi arc states, can be induced in the higher-order nodal-line semimetal by shining circularly polarized light. Moreover, we show that the location of Weyl nodes and the curvature of surface Fermi arcs can be tuned by adjusting the propagation direction and incident angle of light.