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arXiv · 2103.15325

Electronic properties and quasi-particle model of monolayer MoSi$_2$N$_4$

Zhenwei Wang·Xueheng Kuang·Guodong Yu·Peiliang Zhao·Hongxia Zhong·Shengjun Yuan
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Abstract

By a combined study with first-principles calculations and symmetry analysis, we theoretically investigate the electronic properties of monolayer MoSi$_2$N$_4$. While the spin-orbital coupling results in bands splitting, the horizontal mirror symmetry locks the spin polarization along z-direction. In addition, a three-band tight-binding model is constructed to describe the low-energy quasi-particle states of monolayer MoSi$_2$N$_4$, which can be generalized to strained MoSi$_2$N$_4$ and its derivatives. The calculations using the tight-binding model show an undamped $\sqrt{q}$-dependent plasmon mode that agrees well with the results of first-principles calculations. Our model can be extended to be suitable for future theoretical and numerical studies of low-energy properties in MoSi$_2$N$_4$ family materials. Furthermore, the study of electronic properties of monolayer MoSi$_2$N$_4$ paves a way for its applications in spintronics and plasmonics.

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Zhenwei Wang, Xueheng Kuang, Guodong Yu, Peiliang Zhao, Hongxia Zhong, Shengjun Yuan. 2021-03-29. Electronic properties and quasi-particle model of monolayer MoSi$_2$N$_4$. https://doi.org/10.1103/physrevb.104.155110

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