Phonon-limited carrier transport in the Weyl semimetal TaAs

TL;DR

This study uses advanced ab initio calculations to analyze how electron-phonon interactions affect charge transport in the Weyl semimetal TaAs, revealing the impact of Fermi surface topology and doping on conductivity.

Contribution

It provides new insights into the microscopic mechanisms of transport in TaAs, emphasizing the role of Fermi surface features and doping effects on carrier dynamics.

Findings

Excellent agreement with experimental conductivity above 100 K

Small Fermi level shifts significantly alter conductivity

Fermi surface nesting influences scattering and carrier lifetimes

Abstract

Topological Weyl semimetals represent a novel class of quantum materials that exhibit remarkable properties arising from their unique electronic structure. In this work, we employ state-of-the-art ab initio methods to investigate the role of the electron-phonon interactions on the charge transport properties of TaAs. Our calculations of the temperature-dependent electrical conductivity with the iterative Boltzmann transport equation show excellent agreement with experimental measurements above 100 K. Extending the analysis to doped systems, we demonstrate that even small shifts in the Fermi level can lead to substantial changes in conductivity, driven by the complex topology of the Fermi surface. In particular, modifications in Fermi surface nesting emerge as a key factor influencing scattering processes and carrier lifetimes. These findings offer critical insights into the microscopic mechanisms that govern transport in TaAs and highlight the sensitivity of Weyl semimetals to doping and carrier dynamics.