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Point-like topological defects in bilayer quantum Hall systems

Gerardo Cristofano·Vincenzo Marotta·Adele Naddeo·Giuliano Niccoli
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Abstract

Following a suggestion given in Phys. Lett. B 571 (2003) 250, we show how a bilayer Quantum Hall system at fillings nu =m/pm+2 can exhibit a point-like topological defect in its edge state structure. Indeed our CFT theory for such a system, the Twisted Model (TM), gives rise in a natural way to such a feature in the twisted sector. Our results are in agreement with recent experimental findings (cond-mat/0503478) which evidence the presence of a topological defect in the bilayer system.

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Gerardo Cristofano, Vincenzo Marotta, Adele Naddeo, Giuliano Niccoli. 2006-10-26. Point-like topological defects in bilayer quantum Hall systems. https://doi.org/10.1088/1742-5468%2F2006%2F05%2Fl05002

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