论文标题
在非磁电气HF2X中出现的二维磁化（X = S，SE，TE）
Emerging Two-Dimensional Magnetism in Nonmagnetic Electrides Hf2X (X = S, Se, Te)
论文作者
论文摘要
二维（2D）磁体的最新实验发现触发了激烈的研究活动，以寻找原子上薄的磁系统。使用第一原则计算，我们预测单层（MLS），几层和非磁性分层电气HF2X（X = S，SE，TE）的层和表面的出现，由三个厚的HF-X-HF堆栈组成。据揭示，每个大量HF2X都有一个新型的dirac节点线的量子状态，其高密度是由HF -5D阳离子和层间阴离子阴离子电子电子在-0.9 eV左右以下EF以下的-0.9 eV。但是，对于ML，HF2X的几层和表面很少，这种杂交状态转向EF，以产生范霍夫的奇异性，从而导致石不稳定性。所得的表面铁磁剂在HF2X（001）处产生强烈自旋的拓扑表面状态，表明阴离子电子，2D磁性和带拓扑彼此纠缠在一起。我们的发现将通过在非磁性分层电气中利用表面效应来开辟新的观点，以发现2D磁铁。
Recent experimental discoveries of two-dimensional (2D) magnets have triggered intense research activities to search for atomically thin magnetic systems. Using first-principles calculations, we predict the emergence of 2D magnetism in the monolayers (MLs), few layers, and surfaces of nonmagnetic layered electrides Hf2X (X = S, Se, Te) consisting of three-atom-thick Hf-X-Hf stacks. It is revealed that each bulk Hf2X hosts a novel quantum state of Dirac nodal lines with a high density of states arising from Hf-5d cationic and interlayer anionic electrons around -0.9 eV below the Fermi level EF. However, for the MLs, few layers, and surfaces of Hf2X, such hybridized states are shifted toward EF to generate van Hove singularities, leading to a Stoner instability. The resulting surface ferromagnetism gives rise to strongly spin-polarized topological surface states at Hf2X(001), demonstrating that anionic electrons, 2D magnetism, and band topology are entangled with each other. Our findings will open new perspectives for the discovery of 2D magnets via exploiting surface effects in nonmagnetic layered electrides.
