Resistivity and Hall effect of LiFeAs: Evidence for electron-electron scattering

TL;DR

This study investigates the electrical transport properties of LiFeAs, revealing strong electron-electron scattering and a temperature-dependent Hall effect, supported by band structure calculations, highlighting its unique superconducting behavior.

Contribution

The paper provides detailed experimental data and theoretical analysis of resistivity and Hall effect in LiFeAs, emphasizing electron-electron interactions and band structure effects.

Findings

Resistivity exhibits quadratic temperature dependence at low temperatures.

Hall constant is negative and varies with temperature.

Band structure calculations reproduce transport features.

Abstract

LiFeAs is unique among the broad family of FeAs-based superconductors, because it is superconducting with a rather large $T_c\simeq 18$ K under ambient conditions although it is a stoichiometric compound. We studied the electrical transport on a high-quality single crystal. The resistivity shows quadratic temperature dependence at low temperature giving evidence for strong electron-electron scattering and a tendency towards saturation around room temperature. The Hall constant is negative and changes with temperature, what most probably arises from a van Hove singularity close to the Fermi energy in one of the hole-like bands. Using band structure calculations based on angular resolved photoemission spectra we are able to reproduce all the basic features of both the resistivity as well as the Hall effect data.