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

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 نشر من قبل Gabor Csathy
 تاريخ النشر 2014
  مجال البحث فيزياء
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In this work we report the opening of an energy gap at the filling factor $ u=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 $ u=3+1/3$ and $3+1/5$ states from the upper spin branch are reversed when compared to the $ u=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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