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arXiv · 1611.00776

Moiré 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 moiré pattern. Our observation is motivated by the recent observations of fractional quantum Hall incompressible states in moiré-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 moiré potential on many-body states.

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Fengcheng Wu, A. H. MacDonald. 2016-12-10. Moiré Assisted Fractional Quantum Hall State Spectroscopy. https://doi.org/10.1103/physrevb.94.241108

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