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arXiv · 2305.02838

Superconductivity in Mo$_4$Ga$_{20}$As with Endohedral Gallium Clusters

Bin-Bin Ruan·Le-Wei Chen·Yun-Qing Shi·Jun-Kun Yi·Qing-Song Yang·Meng-Hu Zhou·Ming-Wei Ma·Gen-Fu Chen·Zhi-An Ren
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Abstract

We report the discovery and detailed investigation of superconductivity in Mo$_4$Ga$_{20}$As. Mo$_4$Ga$_{20}$As crystallizes in the space group of $I4/m$ (No. 87), with lattice parameters $a$ = 12.86352 \AA and $c$ = 5.30031 \AA. The resistivity, magnetization, and specific heat data reveal Mo$_4$Ga$_{20}$As to be a type-II superconductor with $T_c$ = 5.6 K. The upper and lower critical fields are estimated to be 2.78 T and 22.0 mT, respectively. In addition, electron-phonon coupling in Mo$_4$Ga$_{20}$As is possibly stronger than the BCS weak-coupling limit. First-principles calculations suggest the Fermi level being dominated by the Mo-4$d$ and Ga-4$p$ orbitals.

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Bin-Bin Ruan, Le-Wei Chen, Yun-Qing Shi, Jun-Kun Yi, Qing-Song Yang, Meng-Hu Zhou, Ming-Wei Ma, Gen-Fu Chen, Zhi-An Ren. 2023-05-04. Superconductivity in Mo$_4$Ga$_{20}$As with Endohedral Gallium Clusters. https://doi.org/10.1088/1361-648x/acc3ec

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