Floquet-Engineering Weyl Points and Linked Fermi Arcs from Straight Nodal Lines

TL;DR

This paper demonstrates how circularly polarized light can transform intersecting straight nodal lines in topological semimetals into a novel Weyl phase with linked Fermi arcs, revealing new topological phenomena.

Contribution

It uncovers a new mechanism for creating linked Fermi arcs in Weyl semimetals from straight nodal lines using Floquet engineering, especially when multiple lines intersect.

Findings

Circularly polarized light gaps intersecting straight nodal lines into Weyl points.

Induces surface Fermi arcs that form a linked topological structure.

Proposes potential applications in spin-splitting antiferromagnets and classical systems.

Abstract

Floquet engineering provides a powerful and flexible method for modifying the band structures of quantum materials. While circularly polarized light has been shown to convert curved nodal lines in three-dimensional semimetals into Weyl points, such a transformation is forbidden for an isolated straight nodal line. In this work, we uncover a dramatic shift in this paradigm when multiple straight nodal lines intersect. We observe that circularly polarized light not only gaps them into Weyl points but also induces unprecedented surface-state Fermi arcs that extend across the entire surface Brillouin zone and form a linked topological structure. These findings advance our fundamental understanding of light-driven transitions in topological semimetals and unveil a unique Weyl semimetal phase defined by linked Fermi arcs. We discuss potential exotic phenomena arising from this phase, applications of our predictions to spin-splitting antiferromagnets, and the extension of this Weyl semimetal phase to classical systems.