Resistivity tensor correlations in the mixed state of electron-doped superconductor Nd$_{2-x}$Ce$_x$CuO$_{4+\delta}$

TL;DR

This study investigates the magnetic-field dependence of resistivity and Hall resistance in electron-doped Nd$_{2-x}$Ce$_x$CuO$_{4+ delta}$, revealing a universal scaling relationship and insights into pairing symmetry and disorder effects.

Contribution

It demonstrates a universal resistivity tensor correlation in electron-doped cuprates and links it to pairing symmetry and disorder, advancing understanding of their mixed state properties.

Findings

Universal scaling exponent $eta$=1.5 $ imes$ 0.4 found across samples.

Correlation between resistivity and Hall resistivity analyzed via scaling laws.

Insights into pairing symmetry and disorder effects in electron-doped superconductors.

Abstract

The magnetic-field dependencies of the longitudinal and Hall resistance of the electron-doped compounds Nd$_{2-x}$Ce$_x$CuO$_{4+\delta}$ in underdoped region with $x$=0.14 and with varying degrees of disorder ($\delta$) were investigated. It was established experimentally that the correlation between the longitudinal electrical resistivity and the Hall resistivity can be analyzed on the basis of scaling relationships: $\rho_{xy}$($B$)$\sim$ $\rho^{\beta}_{xx}$($B$). For the totality of the investigated single-crystal films of Nd$_{2-x}$Ce$_x$CuO$_{4+\delta}$/SrTiO$_3$ the universal value $\beta$=1.5 $\pm$0.4 is found. The observed feature in the electron-doped two-dimensional systems can be associated both with a displaying of anisotropic $s$ - wave or $d$-wave pairing symmetry and with a rather strong pinning due to an essential degree of disorder in the samples under study.