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arXiv · 1912.08383

Monolayer NbF$_4$: a $4d^1$-analogue of cuprates

Yang Yang·Wan-Sheng Wang·C. S. Ting·Qiang-Hua Wang
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Abstract

The electronic structure and possible electronic orders in monolayer NbF$_4$ are investigated by density functional theory and functional renormalization group. Because of the niobium-centered octahedra, the energy band near the Fermi level is found to derive from the $4d_{xy}$ orbital, well separated from the other bands. Local Coulomb interaction drives the undoped system into an antiferromagnetic insulator. Upon suitable electron/hole doping, the system is found to develop $d_{x^2-y^2}$-wave superconductivity with sizable transition temperature. Therefore, the monolayer NbF$_4$ may be an exciting $4d^1$ analogue of cuprates, providing a new two-dimensional platform for high-$T_c$ superconductivity.

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Yang Yang, Wan-Sheng Wang, C. S. Ting, Qiang-Hua Wang. 2019-12-18. Monolayer NbF$_4$: a $4d^1$-analogue of cuprates. https://arxiv.org/abs/1912.08383

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