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arXiv · 2104.13533

Fragile Symmetry-Protected Half Metallicity in Two-Dimensional van der Waals Magnets: A Case Study of Monolayer FeCl2

Qiushi Yao·Jiayu Li·Qihang Liu
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Abstract

Two-dimensional (2D) half-metallic materials are of great interest for their promising applications in spintronics. Although numerous of 2D half-metals have been proposed theoretically, rarely of them can be synthesized experimentally. Here, exemplified by monolayer FeCl2, we show three mechanisms in such quantum magnets that would cause the metal-insulator transition by using first-principles calculations. In particular, half-metallicity, especially that protected by symmetry-induced degeneracies, predicted by the previous theoretical simulations could be destroyed by electron correlation, spin-orbit coupling and further structural distortions to lower the total energy. Our work reveals the fragility of the symmetry-protected half-metals upon various competing energy-lowering mechanisms, which should be taken into account for theoretically predicting and designing quantum mateirals with exotic functionalities.

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Qiushi Yao, Jiayu Li, Qihang Liu. 2021-04-28. Fragile Symmetry-Protected Half Metallicity in Two-Dimensional van der Waals Magnets: A Case Study of Monolayer FeCl2. https://doi.org/10.1103/physrevb.104.035108

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