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arXiv · 1601.00824

Effect of impurity scattering on superconductivity in K$_2$Cr$_3$As$_3$

Y. Liu·J. K. Bao·H. K. Zuo·A. Ablimit·Z. T. Tang·C. M. Feng·Z. W. Zhu·G. H. Cao
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Abstract

Impurity scattering in a superconductor may serve as an important probe for the nature of superconducting pairing state. Here we report the impurity effect on superconducting transition temperature $T_\mathrm{c}$ in the newly discovered Cr-based superconductor K$_2$Cr$_3$As$_3$. The resistivity measurements show that the crystals prepared using high-purity Cr metal ($\geq$99.99\%) have an electron mean free path much larger than the superconducting coherence length. For the crystals prepared using impure Cr that contains various \emph{nonmagnetic} impurities, however, the $T_\mathrm{c}$ decreases significantly, in accordance with the generalized Abrikosov-Gor'kov pair-breaking theory. This finding supports a non-$s$-wave superconductivity in K$_2$Cr$_3$As$_3$.

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Y. Liu, J. K. Bao, H. K. Zuo, A. Ablimit, Z. T. Tang, C. M. Feng, Z. W. Zhu, G. H. Cao. 2016-01-05. Effect of impurity scattering on superconductivity in K$_2$Cr$_3$As$_3$. https://doi.org/10.1007/s11433-016-5788-6

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