Suppression of Superconductivity in Single Crystals of UPt_3 by Pd Substitution

TL;DR

This study investigates how Pd substitution in UPt_3 single crystals suppresses superconductivity, revealing a stronger effect than other impurities, possibly linked to changes in magnetic fluctuations.

Contribution

It demonstrates that Pd substitution causes a more rapid suppression of T_c compared to other impurities, highlighting a unique impurity effect in UPt_3.

Findings

T_c varies linearly with residual resistivity r_0.

Pd substitution suppresses T_c more effectively than other impurities.

Suppression correlates with increased inelastic scattering and magnetic fluctuation changes.

Abstract

The suppression of superconductivity by substitution effects has been measured in high quality single crystals of U(Pt_{1-x} Pd_x)_3 with 0 <= x <= 0.002. While the superconducting transition temperature T_c varies linearly with residual resistivity r_0, consistent with pair-breaking by impurity potential scattering, the rate of suppression of T_c with r_0 is much larger for Pd substitution than for other impurity substitutions or by increased defect density. This effect is correlated with an increase in the inelastic scattering coefficient, and may be related to Pd-induced changes in the magnetic fluctuation spectrum.