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arXiv · 2009.02688

Strain-tunable magnetism and nodal loops in monolayer MnB

Chang Liu·Botao Fu·Huabing Yin·Guangbiao Zhang·Chao Dong
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Abstract

Designing two-dimensional (2D) materials with magnetic and topological properties has continuously attracted intense interest in fundamental science and potential applications. Here, on the basis of first-principles calculations, we predict the coexistence of antiferromagnetism and Dirac nodal loop (NL) in the monolayer MnB, where the band crossing points are very close to the Fermi Level. Remarkably, a moderate strain can induce an antiferromagnetic to ferromagnetic phase transition, driving the monolayer MnB to a ferromagnetic metal with Weyl NLs. Such a type of topological quantum phase transition has not been observed before. In addition, the symmetry-protected properties of the two types of NLs as well as the magnetic critical temperatures are investigated. The controllable magnetic and topological order in monolayer MnB offers a unique platform for exploring topological quantum phase transitions and realizing nanospintronic devices.

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Chang Liu, Botao Fu, Huabing Yin, Guangbiao Zhang, Chao Dong. 2020-09-06. Strain-tunable magnetism and nodal loops in monolayer MnB. https://arxiv.org/abs/2009.02688

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