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arXiv · 1112.6393

Berry phase and Anomalous Hall Effect in a Three-orbital Tight-binding Hamiltonian

Yan He·Joel Moore·C. M. Varma
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Abstract

We consider the Anomalous Hall (AH) state induced by interactions in a three-orbital per unit-cell model. To be specific we consider a model appropriate for the Copper-Oxide lattice to highlight the necessary conditions for time-reversal breaking states which are AH states and which are not. We compare the singularities of the wave-functions of the three-orbital model, which are related to the nonzero Berry curvature, and their variation with a change of gauge to those in the two-orbital model introduced in a seminal paper by Haldane. Explicit derivation using wave-functions rather than the more powerful abstract methods may provide additional physical understanding of the phenomena.

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Yan He, Joel Moore, C. M. Varma. 2011-12-29. Berry phase and Anomalous Hall Effect in a Three-orbital Tight-binding Hamiltonian. https://doi.org/10.1103/physrevb.85.155106

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