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arXiv · 1008.5191

Entanglement from Charge Statistics: Exact Relations for Many-Body Systems

H. Francis Song·Christian Flindt·Stephan Rachel·Israel Klich·Karyn Le Hur
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Abstract

We present exact formulas for the entanglement and Rényi entropies generated at a quantum point contact (QPC) in terms of the statistics of charge fluctuations, which we illustrate with examples from both equilibrium and non-equilibrium transport. The formulas are also applicable to groundstate entanglement in systems described by non-interacting fermions in any dimension, which in one dimension includes the critical spin-1/2 XX and Ising models where conformal field theory predictions for the entanglement and Rényi entropies are reproduced from the full counting statistics. These results may play a crucial role in the experimental detection of many-body entanglement in mesoscopic structures and cold atoms in optical lattices.

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H. Francis Song, Christian Flindt, Stephan Rachel, Israel Klich, Karyn Le Hur. 2010-08-31. Entanglement from Charge Statistics: Exact Relations for Many-Body Systems. https://doi.org/10.1103/physrevb.83.161408

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