Tuning from Frustrated Magnetism to Superconductivity in Quasi-One-Dimensional KCr$_3$As$_3$ Through Hydrogen Doping

Keith M. Taddei; Liurukara D. Sanjeewa; Bing-Hua Lei; Yuhao Fu; Qiang Zheng; David J. Singh; Athena S. Sefat; Clarina dela Cruz

doi:10.1103/physrevb.100.220503

arXiv · 1905.03360

Tuning from Frustrated Magnetism to Superconductivity in Quasi-One-Dimensional KCr$_3$As$_3$ Through Hydrogen Doping

Keith M. Taddei·Liurukara D. Sanjeewa·Bing-Hua Lei·Yuhao Fu·Qiang Zheng·David J. Singh·Athena S. Sefat·Clarina dela Cruz

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Abstract

We report the charge doping of KCr$_3$As$_3$ via H intercalation. We show that the previously reported ethanol bath deintercalation of K$_2$Cr$_3$As$_3$ to KCr$_3$As$_3$ has a secondary effect whereby H from the bath enters the quasi-one-dimensional Cr$_6$As$_6$ chains. Furthermore, we find that - contrary to previous interpretations - the difference between non-superconducting as-grown KCr$_3$As$_3$ samples and superconducting hydrothermally annealed samples is not a change in crystallinity but due to charge doping, with the latter treatment increasing the H concentration in the CrAs tubes effectively electron-doping the 133 compound. These results suggest a new stoichiometry KH$_x$Cr$_3$As$_3$, that superconductivity arises from a suppressed magnetic order via a tunable parameter and pave the way for the first charge-doped phase diagram in these materials.

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Keith M. Taddei, Liurukara D. Sanjeewa, Bing-Hua Lei, Yuhao Fu, Qiang Zheng, David J. Singh, Athena S. Sefat, Clarina dela Cruz. 2019-05-08. Tuning from Frustrated Magnetism to Superconductivity in Quasi-One-Dimensional KCr$_3$As$_3$ Through Hydrogen Doping. https://doi.org/10.1103/physrevb.100.220503

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