Evolution of Hall coefficient in two-dimensional heavy fermion CeCoIn$_5$

TL;DR

This study investigates how pressure influences the Hall coefficient in the quasi-2D heavy fermion compound CeCoIn$_5$, revealing insights into its non-Fermi liquid behavior and Fermi surface anisotropies.

Contribution

It provides the first detailed analysis of pressure-dependent Hall coefficient behavior in CeCoIn$_5$, linking it to Fermi surface hot and cold spots and magnetic fluctuations.

Findings

Suppression of Hall coefficient enhancement with pressure

Enhancement confined to intermediate temperatures

Evidence for anisotropic scattering due to antiferromagnetic fluctuations

Abstract

We report on the pressure dependence of the Hall coefficient $R_H$ in quasi-2D heavy fermion CeCoIn$_5$. At ambient pressure, below a temperature associated with the emergence of non-Fermi liquid properties, $R_H$ is anomalously enhanced. We found that the restoration of the Fermi liquid state with applied pressure leads to a gradual suppression of this dramatic enhancement. Moreover, the enhancement in $R_H$ was found to be confined to an intermediate temperature window, where inelastic electron-electron scattering is dominant. Our results strongly support the presence of cold and hot spots on the Fermi surface probably due to anisotropic scattering by antiferromagnetic fluctuations, which may also prove relevant for the debate on the anomalous normal-state properties of high-$T_c$ cuprates.