Thermal plasmon resonantly enhances electron scattering in Dirac/Weyl semimetals

TL;DR

This paper investigates how thermal plasmons resonantly enhance electron scattering in Dirac/Weyl semimetals, revealing a non-monotonic energy dependence and the importance of screening effects.

Contribution

It demonstrates the resonant enhancement of electron scattering due to thermal plasmons and compares Coulomb and Hubbard interactions in Dirac/Weyl semimetals.

Findings

Scattering rate exhibits a sharp peak due to thermal plasmon resonance.

Perturbation theory diverges for Coulomb interaction without screening.

Hubbard interaction is well-described by second-order perturbation theory.

Abstract

We study the inelastic scattering rate due to the Coulomb interaction in three-dimensional Dirac/Weyl semimetals at finite temperature. We show that the perturbation theory diverges because of the long-range nature of the interaction, hence, thermally induced screening must be taken into account. We demonstrate that the scattering rate has a non-monotonic energy dependence with a sharp peak owing to the resonant decay into thermal plasmons. We also consider the Hubbard interaction for comparison. We show that, in contrast to the Coulomb case, it can be well described by the second-order perturbation theory in a wide energy range.