Anomalous Fermi arcs in a periodically driven Weyl system

TL;DR

This paper demonstrates the theoretical construction of anomalous Fermi arcs in a periodically driven Weyl system, showing they can exist without the traditional topological Chern number framework.

Contribution

The authors introduce a model that realizes anomalous Fermi arcs in a driven Weyl system, challenging the conventional understanding tied to Chern numbers.

Findings

Anomalous Fermi arcs can exist without non-zero Chern numbers.

Periodic driving enables new topological surface states.

The model provides a concrete example of these phenomena.

Abstract

Three dimensional Weyl semimetals exhibit open Fermi arcs on their sample surfaces connecting the projection of bulk Weyl points of opposite chirality. The canonical interpretation of these surfaces states is in terms of chiral edge modes of a layer quantum Hall effect: The two-dimensional momentum-space planes perpendicular to the momentum connecting the two Weyl points are characterized by a non-zero Chern number. It might be interesting to note, that in analogy to the known two-dimensional Floquet anomalous chiral edge states, one can realize open Fermi arcs in the absence of Chern numbers in periodically driven system. Here, we present a way to construct such anomalous Fermi arcs in a concrete model.