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arXiv · 2305.03867

Coexistence of Dirac Fermions and Magnons in a Layered Two-Dimensional Semiquinoid Metal-Organic Framework

Christopher Lane·Yixuan Huang·Lin Hou·Jian-Xin Zhu
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Abstract

We predict the magnetic and electronic properties of a novel metal-organic framework. By combining density functional theory and density matrix renormalization group approaches, we find the diatomic Kagome crystal structure of the metal-semiquinoid framework (H$_2$NMe$_2$)$_2$M$_2$(Cl$_2$dhbq)$_3$ (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) to host a rich variety of antiferromagnetic (AFM) and ferromagnetic (FM) Dirac semimetallic, spin-polarized and unpolarized Dirac fermions, along with metallic phases and flat band magnetic insulators. Concomitantly, the spin excitation spectrum of the various magnetic systems display multiple Dirac-like and nodal-ring crossings. This suggests that the metal-semiquinoid system is an ideal platform for examining the intertwining of Dirac fermions and magnons.

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Christopher Lane, Yixuan Huang, Lin Hou, Jian-Xin Zhu. 2023-05-05. Coexistence of Dirac Fermions and Magnons in a Layered Two-Dimensional Semiquinoid Metal-Organic Framework. https://arxiv.org/abs/2305.03867

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