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arXiv · 1710.05597

Phase transition and intrinsic metric of the dipolar fermions in quantum Hall regime

Zi-Xiang Hu·Qi Li·Lin-Peng Yang·Wu-Qing Yang·Na Jiang·Rui-Zhi Qiu·Bo Yang
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Abstract

For the fast rotating quasi-two-dimensional dipolar fermions in the quantum Hall regime, the interaction between two dipoles breaks the rotational symmetry when the dipole moment has component in the the plane via being tuned by an external field. For the anisotropic two-body interaction, we expand it in a generalized pseudopotentials (PPs). With assuming that all the dipoles are polarized in the same direction, we perform the numerical diagonalization for finite size systems on a torus. We find that the most stable fractional quantum Hall (FQH) states in the lowest Landau level (LLL) and the first Landau level (1LL) are ν = 1/3 and ν = 2 + 1/5 Laughlin state respectively in the isotropic case. While rotating the dipolar angle, these FQH states reveal a robustness and finally enter into a molecule phase in which all the particles are attracted and form a bound state. The anisotropy and the phase transition are studied by the intrinsic metric, the wave function overlap and the nematic order parameter.

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Zi-Xiang Hu, Qi Li, Lin-Peng Yang, Wu-Qing Yang, Na Jiang, Rui-Zhi Qiu, Bo Yang. 2017-11-28. Phase transition and intrinsic metric of the dipolar fermions in quantum Hall regime. https://doi.org/10.1103/physrevb.97.035140

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