Mapping a fractional quantum Hall state to a fractional Chern insulator

Yinhan Zhang; Junren Shi

doi:10.1103/physrevb.93.165129

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arXiv · 1510.00524

Mapping a fractional quantum Hall state to a fractional Chern insulator

Yinhan Zhang·Junren Shi

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Abstract

We establish a variational principle for properly mapping a fractional quantum Hall (FQH) state to a fractional Chern insulator (FCI). We find that the mapping has a gauge freedom which could generate a class of FCI ground state wave functions appropriate for different forms of interactions. Therefore, the gauge should be fixed by a variational principle that minimizes the interaction energy of the FCI model. For a soft and isotropic electron-electron interaction, the principle leads to a gauge coinciding with that for maximally localized \emph{two-dimensional} projected Wannier functions of a Landau level.

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Yinhan Zhang, Junren Shi. 2015-10-02. Mapping a fractional quantum Hall state to a fractional Chern insulator. https://doi.org/10.1103/physrevb.93.165129

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