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arXiv · 1412.8186

Observation of Incompressibility at $ν=4/11$ and $ν=5/13$

N. Samkharadze·I. Arnold·L. N. Pfeiffer·K. W. West·G. A. Csáthy
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Abstract

The region of filling factors $1/3<ν<2/5$ is predicted to support new types of fractional quantum Hall states with topological order different from that of the Laughlin-Jain or the Moore-Read states. Incompressibility is a necessary condition for the formation of such novel topological states. We find that at 6.9~mK incompressibility develops only at $ν=4/11$ and $5/13$, while the states at $ν=6/17$ and $3/8$ remain compressible. Our observations at $ν=4/11$ and $5/13$ are first steps towards understanding emergent topological order in these fractional quantum Hall states.

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N. Samkharadze, I. Arnold, L. N. Pfeiffer, K. W. West, G. A. Csáthy. 2014-12-28. Observation of Incompressibility at $ν=4/11$ and $ν=5/13$. https://doi.org/10.1103/physrevb.91.081109

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