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arXiv · 1707.09711

Superconductivity at 5 K in quasi-one-dimensional Cr-based KCr3As3 single crystals

Qing-Ge Mu·Bin-Bin Ruan·Bo-Jin Pan·Tong Liu·Jia Yu·Kang Zhao·Gen-Fu Chen·Zhi-An Ren
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Abstract

Recently a new family of Cr-based A2Cr3As3 (A = K, Rb, Cs) superconductors were reported, which own a rare quasi-one-dimensional (Q1D) crystal structure with infinite (Cr3As3)2- chains and exhibit intriguing superconducting characteristics possibly derived from spin-triplet electron pairing. The crystal structure of A2Cr3As3 is actually a slight variation of the hexagonal TlFe3Te3 prototype although they have different lattice symmetry. Here we report superconductivity in a 133-type KCr3As3 compound that belongs to the latter structure. The single crystals of KCr3As3 were prepared by the deintercalation of K ions from K2Cr3As3 crystals which were grown from a high-temperature solution growth method, and it owns a centrosymmetric lattice in contrast to the non-centrosymmetric K2Cr3As3. After annealing at a moderate temperature, the KCr3As3 crystals show bulk superconductivity at 5 K revealed by electrical resistivity, magnetic susceptibility and heat capacity measurements. The discovery of this KCr3As3 superconductor provides a different structural instance to study the exotic superconductivity in these Q1D Cr-based superconductors.

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Qing-Ge Mu, Bin-Bin Ruan, Bo-Jin Pan, Tong Liu, Jia Yu, Kang Zhao, Gen-Fu Chen, Zhi-An Ren. 2017-07-31. Superconductivity at 5 K in quasi-one-dimensional Cr-based KCr3As3 single crystals. https://doi.org/10.1103/physrevb.96.140504

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