Details of Sample Dependence and Transport Properties of URu2Si2

TL;DR

This study investigates how sample quality affects the transport and thermodynamic properties of URu2Si2, revealing that inhomogeneities influence superconducting and hidden order transitions and challenge Fermi liquid behavior.

Contribution

It provides new insights into the dependence of transition temperatures and resistivity behavior on sample quality and pressure inhomogeneity in URu2Si2.

Findings

Resistivity does not follow T^2 dependence in high-quality samples above TSC.

Residual inhomogeneous superconductivity can obscure T^2 behavior.

Hidden order phase is highly sensitive to pressure inhomogeneity.

Abstract

Resistivity and specific heat measurements were performed in the low carrier unconventional superconductor URu2Si2 on various samples with very different qualities. The superconducting transition temperature (TSC) and the hidden order transition temperature (THO) of these crystals were evaluated as a function of the residual resistivity ratio (RRR). In high quality single crystals the resistivity does not seem to follow a T2 dependence above TSC, indicating that the Fermi liquid regime is restricted to low temperatures. However, an analysis of the isothermal longitudinal magnetoresistivity points out that the T2 dependence may be "spoiled" by residual inhomogeneous superconducting contribution. We discuss a possible scenario concerning the distribution of TSC related with the fact that the hidden order phase is very sensitive to the pressure inhomogeneity.