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arXiv · 2101.03352

Quarter-filled Kane-Mele Hubbard model: Dirac half-metals

Simon Mellaerts·Ruishen Meng·Valeri Afanasiev·Jin Won Seo·Michel Houssa·Jean-Pierre Locquet
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Abstract

Recent experimental success in the realization of two-dimensional (2D) magnetism has stimulated the search for new magnetic 2D materials with strong magnetic anisotropy and high Curie temperature. One promising subgroup of 2D magnetic systems are Dirac half-metals (DHM) which have gained a lot of interest recently, as they host a high-temperature quantum anomalous Hall effect (QAHE). This article discusses predictions for intrinsic DHMs and identifies them as realizations of the Kane-Mele Hubbard model at quarter filling. This proposed unification contributes to a firmer understanding of these materials and suggests pathways for the discovery of new DHM systems.

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Simon Mellaerts, Ruishen Meng, Valeri Afanasiev, Jin Won Seo, Michel Houssa, Jean-Pierre Locquet. 2021-01-09. Quarter-filled Kane-Mele Hubbard model: Dirac half-metals. https://doi.org/10.1103/physrevb.103.155159

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