Electron-phonon interaction and zero-field charge carrier transport in the nodal-line semimetal ZrSiS

TL;DR

This study uses first-principles calculations to analyze electron-phonon interactions in ZrSiS, revealing weak coupling, anisotropic resistivity, and good agreement with experimental data, advancing understanding of charge transport in nodal-line semimetals.

Contribution

It provides the first detailed first-principles analysis of electron-phonon interactions and transport properties in ZrSiS, highlighting weak coupling and anisotropic resistivity.

Findings

Weak electron-phonon coupling (~0.1) is energy-independent.

Resistivity is highly anisotropic with a ratio of ~7.5.

Calculated resistivity at 300K matches experimental data.

Abstract

We study electron-phonon interaction and related transport properties of nodal-line semimetal ZrSiS using first-principles calculations. We find that ZrSiS is characterized by a weak electron-phonon coupling on the order of 0.1, which is almost energy independent. The main contribution to the electron-phonon coupling originates from long-wavelength optical phonons, causing no significant renormalization of the electron spectral function. At the charge neutrality point, we find that electrons and holes provide a comparable contribution to the scattering rate. The phonon-limited resistivity calculated within the Boltzmann transport theory is found to be strongly direction-dependent with the ratio between out-of-plane and in-plane directions being $\rho_{zz}/\rho_{xx}\sim 7.5$, mainly determined by the anisotropy of carrier velocities. We estimate zero-field resistivity to be $\rho_{xx}\approx12$ $\mu\Omega$ cm at 300 K, which is in good agreement with experimental data. Relatively small resistivity in ZrSiS can be attributed to a combination of weak electron-phonon coupling and high carrier velocities.