Influence of carrier lifetime on quantum criticality and superconducting Tc of (TMTSF)_2ClO_4

TL;DR

This study investigates how carrier lifetime and nonmagnetic disorder affect quantum criticality and superconductivity in the organic superconductor (TMTSF)$_2$ClO$_4$, revealing a limited change in resistivity behavior despite suppression of $T_c$.

Contribution

It provides new insights into the interplay between disorder, quantum criticality, and superconductivity in organic conductors, supported by resistivity data and theoretical analysis.

Findings

Resistivity's T-linear term decreases with disorder

Superconducting $T_c$ is suppressed beyond a threshold disorder

Scaling between resistivity and $T_c$ breaks down under disorder

Abstract

This work presents and analyzes electrical resistivity data on the organic superconductor (TMTSF)$_2$ClO$_4$ and their anion substituted alloys (TMTSF)$_2$(ClO$_4$)$_{1-x}$(ReO$_4$)$_x$ along the least conducting $c^\star$ axis. Nonmagnetic disorder introduced by finite size domains of anion ordering on non Fermi liquid character of resistivity is investigated near the conditions of quantum criticality. The evolution of the $T$-linear resistivity term with anion disorder shows a limited decrease in contrast with the complete suppression of the critical temperature $T_c$ as expected for unconventional superconductivity beyond a threshold value of $x$. The resulting breakdown of scaling between both quantities is compared to the theoretical predictions of a linearized Boltzmann equation combined to the scaling theory of umklapp scattering in the presence of disorder induced pair-breaking for the carriers.