Antiferromagnetic Chern insulator in centrosymmetric systems

Article

关键词: QUANTIZED HALL CONDUCTANCE;    BOSE-EINSTEIN CONDENSATION;    MEAN-FIELD THEORY;    OPTICAL-ABSORPTION;    SQUARE LATTICE;    TRANSITION;    MODEL;    REALIZATION;    ELECTRONS;   

DOI  :  10.1103/PhysRevB.106.205107

来源: SCIE

【 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 a promising candidate for a strong magnetic blueshift of the charge gap below the Neel temperature and for realizing the quantum anomalous Hall effect at higher temperatures so that applications for data processing become possible.

【 授权许可】

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