The Density of Surface States in Weyl Semimetals

TL;DR

This paper investigates the spectral properties of surface electron states in Weyl semimetals, revealing a universal density of states behavior with a logarithmic singularity at zero energy, linear decrease at intermediate energies, and a square root decay near the band edge.

Contribution

It provides a detailed analysis of the surface state density in Weyl semimetals, highlighting universal features linked to their topological order.

Findings

Density of surface states has a logarithmic singularity at zero energy.

Surface state density decreases linearly at intermediate energies.

Density approaches zero as the square root near the band edge.

Abstract

Weyl semimetal is a three-dimensional material with a conical spectrum near an even number of point nodes, where two bands touch each other. Here we study spectral properties of surface electron states in such a system. We show that the density of surface states possesses a logarithmic singularity for the energy $\varepsilon \to 0$. It decreases linearly at the intermediate energy of surface electron states and approaches zero as $\sqrt{1-\varepsilon}$ for $\varepsilon \to 1$. This universal behavior is a hallmark of the topological order that offers a new wide range of applications.