Charge density waves in Weyl semimetals

TL;DR

This paper develops a theoretical framework for charge density wave states in Weyl semimetals, highlighting a unique topological CDW state with potential links to fractional quantum Hall phenomena.

Contribution

It introduces a novel topological charge density wave state in Weyl semimetals occurring at a specific node separation, connecting it to fractional quantum Hall states.

Findings

The shortest-period CDW state has unique topological properties.

This state occurs when Weyl node separation equals half a reciprocal lattice vector.

Connection established between Weyl CDW states and fractional quantum Hall states.

Abstract

We present a theory of charge density wave (CDW) states in Weyl semimetals and their interplay with the chiral anomaly. In particular, we demonstrate a special nature of the shortest-period CDW state, which is obtained when the separation between the Weyl nodes equals exactly half a primitive reciprocal lattice vector. Its topological properties are shown to be distinct from all other Weyl CDW states. We make a connection between this observation and the three-dimensional fractional quantum Hall state, which was recently proposed to exist in magnetic Weyl semimetals.