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arXiv · 1410.6571

Anomalous Gap Reversal of the $3+1/3$ and $3+1/5$ Fractional Quantum Hall States

Ethan Kleinbaum·Ashwani Kumar·L. N. Pfeiffer·K. W. West·G. A. Csáthy
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Abstract

In this work we report the opening of an energy gap at the filling factor $ν=3+1/3$, firmly establishing the ground state as a fractional quantum Hall state. This and other odd-denominator states unexpectedly break particle-hole symmetry. Specifically, we find that the relative magnitudes of the energy gaps of the $ν=3+1/3$ and $3+1/5$ states from the upper spin branch are reversed when compared to the $ν=2+1/3$ and $2+1/5$ counterpart states in the lower spin branch. Our findings raise the possibility that the former states have a non-conventional origin.

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Ethan Kleinbaum, Ashwani Kumar, L. N. Pfeiffer, K. W. West, G. A. Csáthy. 2014-10-24. Anomalous Gap Reversal of the $3+1/3$ and $3+1/5$ Fractional Quantum Hall States. https://doi.org/10.1103/physrevlett.114.076801

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