Quantum Anomalous Hall Effect from Inverted Charge Transfer Gap

@article{Devakul2021QuantumAH,
  title={Quantum Anomalous Hall Effect from Inverted Charge Transfer Gap},
  author={Trithep Devakul and Liang Fu},
  journal={Physical Review X},
  year={2021}
}
A general mechanism is presented by which topological physics arises in strongly correlated systems without flat bands. Starting from a charge transfer insulator, topology emerges when the charge transfer energy between the cation and anion is reduced to invert the lower Hubbard band and the spin-degenerate charge transfer band. A universal low-energy theory is developed for the inversion of charge transfer gap in a quantum antiferromagnet. The inverted state is found to be a quantum anomalous… 

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