Conductance oscillation in surface junctions of Weyl semimetals

TL;DR

This paper predicts conductance oscillations in Weyl semimetal surface junctions caused by Fermi arc states, with oscillation visibility influenced by Fermi arc shape, orientation, and magnetic fields, providing a new way to identify surface states.

Contribution

It introduces a novel method to detect Fermi arc surface states via conductance oscillations in surface junctions of Weyl semimetals, highlighting the role of magnetic fields and Fermi arc geometry.

Findings

Conductance oscillations depend on Fermi arc shape and orientation.

Magnetic fields enhance oscillation visibility via Weyl orbits.

Surface junctions can serve as platforms for 2D conductance oscillation.

Abstract

Fermi arc surface states, the manifestation of the bulk-edge correspondence in Weyl semimetals, have attracted much research interest. In contrast to the conventional Fermi loop, the disconnected Fermi arcs provide an exotic 2D system for exploration of novel physical effects on the surface of Weyl semimetals. Here, we propose that visible conductance oscillation can be achieved in the planar junctions fabricated on the surface of Weyl semimetal with a pair of Fermi arcs. It is shown that Fabry-P\'{e}rot-type interference inside the 2D junction can generate conductance oscillation with its visibility strongly relying on the shape of the Fermi arcs and their orientation relative to the strip electrodes, the latter clearly revealing the anisotropy of the Fermi arcs. Moreover, we show that the visibility of the oscillating pattern can be significantly enhanced by a magnetic field perpendicular to the surface taking advantage of the bulk-surface connected Weyl orbits. Our work offers an effective way for the identification of Fermi arc surface states through transport measurement and predicts the surface of Weyl semimetal as a novel platform for the implementation of 2D conductance oscillation.