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arXiv · 2310.11810

Quadratic nodal point in a two-dimensional noncollinear antiferromagnet

Xukun Feng·Zeying Zhang·Weikang Wu·Xian-Lei Sheng·Shengyuan A. Yang
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Abstract

Quadratic nodal point (QNP) in two dimensions has so far been reported only in nonmagnetic materials and in the absence of spin-orbit coupling. Here, by first-principles calculations and symmetry analysis, we predict stable QNP near Fermi level in a two-dimensional kagome metal-organic framework material, Cr$_3$(HAB)$_2$, which features noncollinear antiferromagnetic ordering and sizable spin-orbit coupling. Effective kp and lattice models are constructed to capture such magnetic QNPs. Besides QNP, we find Cr$_3$(HAB)$_2$ also hosts six magnetic linear nodal points protected by mirror as well as $C_{2z}T$ symmetry. Properties associated to these nodal points, such as topological edge states and quantized optical absorbance, are discussed.

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Xukun Feng, Zeying Zhang, Weikang Wu, Xian-Lei Sheng, Shengyuan A. Yang. 2023-10-18. Quadratic nodal point in a two-dimensional noncollinear antiferromagnet. https://arxiv.org/abs/2310.11810

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