论文标题
二维分层电气GD $ _2 $ C
Ferromagnetic Weyl Fermions in Two-Dimensional Layered Electride Gd$_2$C
论文作者
论文摘要
最近，二维分层电气已经成为一类新的材料，它们在阳离子层之间的间隙空间中具有阴离子电子层。在这里，根据第一原理的计算，我们在独特的二维分层铁磁（FM）电气GD $ _2 $ c中发现了一个时间逆向对称性的Weyl半学相。据揭示，晶体场将间质电子状态和GD 5 $ d $轨道混合在费米能量附近，形成带反转。同时，FM顺序诱导了两条稀疏的Weyl淋巴结线（WNL），它们通过自旋轨道耦合转换为多对Weyl节点。此外，我们不仅鉴定了连接Weyl节点的Fermi-Arc表面状态，而且还可以预测由于Gapped WNL产生的浆果曲率而导致的固有固有霍尔电导率。我们的发现表明，在室温FM电气GD $ _2 $ C中存在Weyl Fermions，因此提供了一个新的平台来研究电气材料与磁性Weyl Physics之间有趣的相互作用。
Recently, two-dimensional layered electrides have emerged as a new class of materials which possess anionic electron layers in the interstitial spaces between cationic layers. Here, based on first-principles calculations, we discover a time-reversal-symmetry-breaking Weyl semimetal phase in a unique two-dimensional layered ferromagnetic (FM) electride Gd$_2$C. It is revealed that the crystal field mixes the interstitial electron states and Gd 5$d$ orbitals near the Fermi energy to form band inversions. Meanwhile, the FM order induces two spinful Weyl nodal lines (WNLs), which are converted into multiple pairs of Weyl nodes through spin-orbit coupling. Further, we not only identify Fermi-arc surface states connecting the Weyl nodes but also predict a large intrinsic anomalous Hall conductivity due to the Berry curvature produced by the gapped WNLs. Our findings demonstrate the existence of Weyl fermions in the room-temperature FM electride Gd$_2$C, therefore offering a new platform to investigate the intriguing interplay between electride materials and magnetic Weyl physics.
