# Electric field manipulation of surface states in topological semimetals

## TL;DR

This paper analyzes how perpendicular electric fields influence surface states in topological semimetal thin films, revealing shifts in dispersion, Fermi velocity renormalization, and altered surface state decay, affecting quantum transport.

## Contribution

It introduces an analytical perturbation theory approach to study electric field effects on surface states in Weyl and Dirac semimetals, validated by numerical calculations.

## Key findings

- Electric fields shift dispersion relations.
- Fermi velocity is renormalized by electric fields.
- Surface state decay properties are modified.

## Abstract

We investigate the consequences of applying electric fields perpendicularly to thin films of topological semimetals. In particular, we consider Weyl and Dirac semimetals in a configuration such that their surface Fermi arcs lie on opposite edges of the films. We develop an analytical approach based on perturbation theory and a single-surface approximation and we compare our analytical results with numerical calculations. The effect of the electric field on the dispersion is twofold: it shifts the dispersion relation and renormalizes the Fermi velocity, which would, in turn, have direct effects on quantum transport measurements. Additionally, it modifies the spatial decay properties of surface states which will impact the connection of the Fermi arcs in opposite sides of a narrow thin film.