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arXiv · 1611.00776

Moir\'e Assisted Fractional Quantum Hall State Spectroscopy

Fengcheng Wu·A. H. MacDonald
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Abstract

Intra-Landau level excitations in the fractional quantum Hall regime are not accessible via optical absorption measurements. We point out that optical probes are enabled by the periodic potentials produced by a moir\'e pattern. Our observation is motivated by the recent observations of fractional quantum Hall incompressible states in moir\'e-patterned graphene on a hexagonal boron nitride substrate, and is theoretically based on $f-$sum rule considerations supplemented by a perturbative analysis of the influence of the moir\'e potential on many-body states.

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Fengcheng Wu, A. H. MacDonald. 2016-11-02. Moir\'e Assisted Fractional Quantum Hall State Spectroscopy. https://doi.org/10.1103/physrevb.94.241108

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