Reconstruction of Surface Electron Spectrum and Cyclotron Motion in the Charge Density Wave Phase of Weyl Semimetals

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, 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 Δ 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 Δ.