Reconstruction of surface electron spectrum and cyclotron motion in the CDW phase of Weyl semimetals

TL;DR

This paper investigates how charge density wave phases alter the surface electron spectrum in Weyl semimetals, revealing reconnection of Fermi arcs into loops or patterns and analyzing resulting cyclotron motion under magnetic fields.

Contribution

It provides a detailed analysis of surface electron spectrum reconstruction in Weyl semimetals with CDW, including the effects on Fermi arc topology and cyclotron motion characteristics.

Findings

Fermi arcs reconnect into closed loops or patterns in the CDW phase.

Cyclotron frequency depends on electron energy and CDW gap magnitude.

Cyclotron period inversely proportional to the CDW gap for weak coupling.

Abstract

Charge density wave (CDW) instability drastically affects the surface electron spectrum of a Weyl semimetal. We show that in the CDW phase, the Fermi arcs reconnect into either closed Fermi loops or Frieze patterns traversing the reconstructed surface mini-Brillouin zone. For the closed reconnection topology, the application of an out-of-plane magnetic field leads to a cyclotron motion of the surface electrons. We determine the cyclotron frequency as a function of the electron energy and the magnitude of the CDW gap $\Delta$ for various orientations of the Fermi arcs. For weak coupling, the period of cyclotron motion is dominated by the time of traversal of the arc reconnection regions and is inversely proportional to $\Delta$.