论文标题
Kagome量子异常效应，具有高陈数和较大的带隙
Kagome quantum anomalous Hall effect with high Chern number and large band gap
论文作者
论文摘要
由于潜在的应用在低功率消费型自旋装置中，量子异常效应（QAHE）在过去几十年来引起了极大的关注。但是，到目前为止，Qahe仅在非常低的温度下的Chern数字C = 1和2的拓扑绝缘子中进行实验观察到。在这里，我们提出了三个新颖的二维稳定Kagome Ferromagnets CO3PB3S2，CO3PB3SE2和CO3SN3SE2，可以意识到Qahe具有较高的Chern数量| C | = 3。单层CO3PB3S2，CO3PB3SE2和CO3SN3SE2的较大带隙分别为70、77和63 MEV，居里温度TC分别为51、42和46 K。通过构建异质结构CO3SN3SE2/MOS2，其TC增强到60 K，由于界面的拉伸应变为2％，因此带隙可保持约60 MEV。对于双层化合物CO6SN5SE4，它变成半米，其异常的霍尔电导率相对平坦，与| C |相对应= 3附近费米级。我们的结果提供了具有高Chern数量的Qahe的Kagome铁磁单层和异质质的新的拓扑非平地系统| C | = 3和较大的带隙。
Due to the potential applications in the low-power-consumption spintronic devices, the quantum anomalous Hall effect (QAHE) has attracted tremendous attention in past decades. However, up to now, QAHE was only observed experimentally in topological insulators with Chern numbers C= 1 and 2 at very low temperatures. Here, we propose three novel two-dimensional stable kagome ferromagnets Co3Pb3S2, Co3Pb3Se2and Co3Sn3Se2that can realize QAHE with high Chern number of |C|=3. Monolayers Co3Pb3S2, Co3Pb3Se2 and Co3Sn3Se2 possess the large band gap of 70, 77 and 63 meV with Curie temperature TC of 51, 42 and 46 K, respectively. By constructing a heterostructure Co3Sn3Se2/MoS2, its TC is enhanced to 60 K and the band gap keeps about 60 meV due to the tensile strain of 2% at the interface. For the bilayer compound Co6Sn5Se4, it becomes a half-metal, with a relatively flat plateau in its anomalous Hall conductivity corresponding to |C| = 3 near the Fermi level. Our results provide new topological nontrivial systems of kagome ferromagnetic monolayers and heterostructrues possessing QAHE with high Chern number |C| = 3 and large band gaps.
