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arXiv · 1801.01010

Ion-exchange synthesis and superconductivity at 8.6 K of Na2Cr3As3 with quasi-one-dimensional crystal structure

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

A new Cr-based quasi-one-dimensional superconductor Na2Cr3As3 was synthesized by an ion-exchange method in sodium naphthalenide solution. The crystals are thread-like and the structure was analyzed by X-ray diffraction with a noncentrosymmetric hexagonal space group P-6m2 (No. 187), in which the (Cr3As3)2- linear chains are separated by Na+ ions, and the refined lattice parameters are a = 9.239(2) {\AA} and c = 4.209(6) {\AA}. The measurements for electrical resistivity, magnetic susceptibility, and heat capacity reveal a superconducting transition with unconventional characteristic at the Tc of 8.6 K, which exceeds that of all previously reported 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. 2018-01-03. Ion-exchange synthesis and superconductivity at 8.6 K of Na2Cr3As3 with quasi-one-dimensional crystal structure. https://doi.org/10.1103/physrevmaterials.2.034803

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