arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1809.09265cond-mat.mtrl-scicond-mat.mes-hall
收藏

铁磁/拓扑绝缘体/反铁磁异质结构中的轴子绝缘体态

Axion Insulator State in a Ferromagnet/Topological Insulator/Antiferromagnet Heterostructure

Y. S. Hou, R. Q. Wu

摘要:

我们建议使用铁磁绝缘体MnBi_2Se_4/Bi_2Se_3/反铁磁绝缘体Mn_2Bi_2Se_5异质结构来实现轴子绝缘体态。重要的是,这种异质结构中的轴子绝缘体状态仅取决于铁磁绝缘体的磁化强度,因此可以在宽范围的外部磁场中观察到。使用密度泛函计算和模型哈密顿模拟,我们发现,顶部和底部表面有相反的半量子霍尔电导,与一个相当大的全球自旋间隙为5.1毫电子伏开放的拓扑表面状态的Bi 2Se 3。我们的工作提供了一个新的策略,通过使用范德瓦尔斯反铁磁绝缘体以及三维拓扑绝缘体的轴子绝缘体的搜索。

英文摘要:

We propose to use ferromagnetic insulator MnBi2Se4/Bi2Se3/antiferromagnetic insulator Mn2Bi2Se5 heterostructures for the realization of the axion insulator state. Importantly, the axion insulator state in such heterostructures only depends on the magnetization of the ferromagnetic insulator and hence can be observed in a wide range of external magnetic field. Using density functional calculations and model Hamiltonian simulations, we find that the top and bottom surfaces have opposite half-quantum Hall conductance, with a sizable global spin gap of 5.1 meV opened for the topological surface states of Bi2Se3. Our work provides a new strategy for the search of axion insulators by using van der Waals antiferromagnetic insulators along with three-dimensional topological insulators.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑