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arXiv · hep-th/0212318

Twisted CFT and bilayer Quantum Hall systems

G. Cristofano·V. Marotta·A. Naddeo
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Abstract

We identify the impurity interactions of the recently proposed CFT description of a bilayer Quantum Hall system at filling nu =m/(pm+2) in Mod. Phys. Lett. A 15 (2000) 1679. Such a CFT is obtained by m-reduction on the one layer system, with a resulting pairing symmetry and presence of quasi-holes. For the m=2 case boundary terms are shown to describe an impurity interaction which allows for a localized tunnel of the Kondo problem type. The presence of an anomalous fixed point is evidenced at finite coupling which is unstable with respect to unbalance and flows to a vacuum state with no quasi-holes.

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G. Cristofano, V. Marotta, A. Naddeo. 2002-12-27. Twisted CFT and bilayer Quantum Hall systems. https://doi.org/10.1016/j.physletb.2003.04.001

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