Boundary Conditions of Weyl Semimetals

TL;DR

This paper reveals that the boundary conditions of Weyl semimetals are governed by a single parameter, influencing edge states and Fermi arcs, and introduces a new topological number linked to these boundary conditions.

Contribution

It establishes that a single real parameter determines boundary conditions in Weyl semimetals and uncovers a new topological number associated with this parameter.

Findings

Boundary conditions are dictated by one real parameter.

Edge state dispersions depend on this boundary parameter.

A new topological number is identified in the parameter space.

Abstract

We find that generic boundary conditions of Weyl semimetal is dictated by only a single real parameter, in the continuum limit. We determine how the energy dispersions (the Fermi arcs) and the wave functions of edge states depend on this parameter. Lattice models are found to be consistent with our generic observation. Furthermore, the enhanced parameter space of the boundary condition is shown to support a novel topological number.