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arXiv 2209.04730cond-mat.str-elcond-mat.quant-gas
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中心对称系统中的反铁磁Chern绝缘体

Antiferromagnetic Chern insulator in centrosymmetric systems

Morad Ebrahimkhas, Götz S. Uhrig, Walter Hofstetter, Mohsen Hafez-Torbati

摘要:

如果时间反演对电子态的影响不能通过空间群操作补偿,则反铁磁陈氏绝缘体(AFCI)可以存在。通过Kane-Mele-哈伯德模型,在非中心对称蜂窝结构中已经实现了具有共线磁序的AFCI态.在本文中,我们证明了共线AFCI的存在性在正方形格子模型,保持反演对称性。我们的研究依赖于时间反演不变的Harper-Hofstadter-哈伯德模型扩展的次近邻跳跃项,包括自旋轨道耦合和棋盘势。我们发现,在棋盘格势足够大的情况下,在弱排斥作用下的带绝缘体和强排斥作用下的易$xy$平面AF莫特绝缘体之间出现易$z$轴AFCI.我们的结果和非中心对称的Kane-Mele-哈伯德模型的结果之间的密切相似性表明AFCI是自旋轨道耦合和强电子关联的一般结果,它存在于特定的模型或晶格结构之外。一个AFCI的电子和磁性起源于相同的强相互作用的电子是一个有前途的候选人的强磁蓝移的电荷间隙低于内尔温度和实现量子反常霍尔效应在更高的温度,使数据处理的应用成为可能。

英文摘要:

An antiferromagnetic Chern insulator (AFCI) can exist if the effect of the time-reversal transformation on the electronic state cannot be compensated by a space group operation. The AFCI state with collinear magnetic order is already realized in noncentrosymmetric honeycomb structures through the Kane-Mele-Hubbard model. In this paper, we demonstrate the existence of the collinear AFCI in a square lattice model which preserves the inversion symmetry. Our study relies on the time-reversal-invariant Harper-Hofstadter-Hubbard model extended by a next-nearest-neighbor hopping term including spin-orbit coupling and a checkerboard potential. We show that an easy $z$-axis AFCI appears between the band insulator at weak and the easy $xy$-plane AF Mott insulator at strong Hubbard repulsion provided the checkerboard potential is large enough. The close similarity between our results and the results obtained for the noncentrosymmetric Kane-Mele-Hubbard model suggests the AFCI as a generic consequence of spin-orbit coupling and strong electronic correlation which exists beyond a specific model or lattice structure. An AFCI with the electronic and the magnetic properties originating from the same strongly interacting electrons is promising candidate for a strong magnetic blue shift of the charge gap below the Néel temperature and for realizing the quantum anomalous Hall effect at higher temperatures so that applications for data processing become possible.

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。

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