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arXiv · 1711.09617

On the charge and magnetic ordering in monolayer NbSe$_2$: a first principles study

Feipeng Zheng·Zhimou Zhou·Xiaoqiang Liu·Ji Feng
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Abstract

Monolayer NbSe$_2$ has recently been shown to be a 2-dimensional superconductor, with a competing charge-density wave (CDW) order. This work investigates the electronic structure of monolayer NbSe$_2$ based on first principles calculations, focusing on charge and magnetic orders in connection to the superconductivity. It is found that decreased screening in the monolayer NbSe$_2$ with a perfect lattice exhibits magnetic instability, which is removed by the formation of CDW. Two energetically competitive but distinct $3\times3$ CDW structures are revealed computationally, which have a significant impact on the Fermi surface. The relations of the potential CDW phases with experimental structure and the coexisting superconductivity are discussed.

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Feipeng Zheng, Zhimou Zhou, Xiaoqiang Liu, Ji Feng. 2017-12-22. On the charge and magnetic ordering in monolayer NbSe$_2$: a first principles study. https://doi.org/10.1103/physrevb.97.081101

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