Wavefunction approach to the fractional anomalous Hall crystal

Tixuan Tan; Julian May-Mann; Trithep Devakul

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arXiv · 2409.06775

Wavefunction approach to the fractional anomalous Hall crystal

Tixuan Tan·Julian May-Mann·Trithep Devakul

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Abstract

We propose fractional anomalous Hall crystals (FAHCs) as possible ground states of strongly interacting electrons in parent bands with Berry curvature. FAHCs are exotic states of matter that spontaneously break continuous translation symmetry to form a fractional Chern insulator. We construct a unified family of variational wavefunctions that describe FAHCs and their competing states in the presence of uniform parent Berry curvature. We calculate their variational energy with Coulomb interactions semi-analytically in the thermodynamic limit. Our analysis reveals that FAHCs can be energetically favorable over both Wigner crystals and integer anomalous Hall crystals for sufficiently strong interactions or flat dispersion.

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Tixuan Tan, Julian May-Mann, Trithep Devakul. 2024-09-10. Wavefunction approach to the fractional anomalous Hall crystal. https://arxiv.org/abs/2409.06775

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