论文标题
二维金属有机框架中的Chern绝缘子和高咖喱温度半金属
Chern insulators and high Curie temperature Dirac half-metal in two-dimensional metal-organic frameworks
论文作者
论文摘要
最近，具有非平凡拓扑状态的二维（2D）磁性材料引起了人们的关注。其中，2D金属有机框架（MOF）由于其优势而脱颖而出，例如实践中的易于合成，对氧化的敏感性较小，与无机材料截然不同。通过密度功能理论计算，我们系统地研究了2D MOFS X（C21H15N3）类的电子和拓扑特性（X =过渡金属元件从3D到5D）。令人兴奋的是，我们发现X（C21H15N3）（X = Ti，Zr，Ag，Au）是具有较大带隙（〜7.1 MEV）的Chern绝缘子。通过研究一个四波段有效的模型，可以发现X（C21H15N3）中的Chern绝缘体阶段（X = Ti，Zr，Ag，Au）是由C21H15N3分子的P轨道的频段反转引起的。此外，MN（C21H15N3）是一个狄拉克半金属的铁磁铁，高达156 K的居里温度。我们的工作表明，2D MOFS X（C21H15N3）是实现量子异常霍尔效应和设计基于高速和长距离使用的一半型传播的量子异常效应和设计的量子异常效果和设计的良好平台。
Two-dimensional (2D) magnetic materials with nontrivial topological states have drawn considerable attention recently. Among them, 2D metal-organic frameworks (MOFs) are standing out due to their advantages, such as the easy synthesis in practice and less sensitivity to oxidation that are distinctly different from inorganic materials. By means of density-functional theory calculations, we systematically investigate the electronic and topological properties of a class of 2D MOFs X(C21H15N3) (X = transition metal element from 3d to 5d). Excitingly, we find that X(C21H15N3) (X = Ti, Zr, Ag, Au) are Chern insulators with sizable band gaps (~7.1 meV). By studying a four-band effective model, it is revealed that the Chern insulator phase in X(C21H15N3) (X = Ti, Zr, Ag, Au) is caused cooperatively by the band inversion of the p orbitals of the C21H15N3 molecule and the intrinsic ferromagnetism of X(C21H15N3). Additionally, Mn(C21H15N3) is a Dirac half-metal ferromagnet with a high Curie temperature up to 156 K. Our work demonstrates that 2D MOFs X(C21H15N3) are good platforms for realizing Quantum anomalous Hall effect and designing novel spintronic devices based on half-metals with high-speed and long-distance spin transport.
