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arXiv · 2207.12031

Topological and nodal superconductor kagome magnesium triboride

Yipeng An·Juncai Chen·Zhengxuan Wang·Jie Li·Shijing Gong·Chunlan Ma·Tianxing Wang·Zhaoyong Jiao·Ruqian Wu·Jiangping Hu·Wuming Liu
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Abstract

Recently the kagome compounds have inspired enormous interest and made some great progress such as in the field of superconductivity and topology. Here we predict a different kagome magnesium triboride (MgB3) superconductor with a calculated Tc ~12.2 K and Tc ~15.4 K by external stress, the potentially highest among the reported diverse kagome-type superconductors. We reveal its various exotic physical properties including the van Hove singularity, flat-band, multiple Dirac points, and nontrivial topology. The system can be described by a two-band model with highly anisotropic superconducting gaps on Fermi surfaces. Its topological and nodal superconducting nature is unveiled by a recently developed symmetry indicators method. Our results suggest that MgB3 can be a new platform to study exotic physics in the kagome structure, and pave a way to seek for more superconductors and topological materials with XY3-type kagome lattice.

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Yipeng An, Juncai Chen, Zhengxuan Wang, Jie Li, Shijing Gong, Chunlan Ma, Tianxing Wang, Zhaoyong Jiao, Ruqian Wu, Jiangping Hu, Wuming Liu. 2023-01-28. Topological and nodal superconductor kagome magnesium triboride. https://doi.org/10.1103/physrevmaterials.7.014205

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