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arXiv · 1512.08132

Charged Entanglement Entropy of Local Operators

Pawel Caputa·Masahiro Nozaki·Tokiro Numasawa
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Abstract

In this work we consider the time evolution of charged Renyi entanglement entropies after exciting the vacuum with local fermionic operators. In order to explore the information contained in charged Renyi entropies, we perform computations of their excess due to the operator excitation in 2d CFT, free fermionic field theories in various dimensions as well as holographically. In the analysis we focus on the dependence on the entanglement charge, the chemical potential and the spacetime dimension. We find that excesses of charged (Renyi) entanglement entropy can be interpreted in terms of charged quasiparticles. Moreover, we show that by appropriately tuning the chemical potential charged Renyi entropies can be used to extract entanglement in a certain charge sector of the excited state.

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Pawel Caputa, Masahiro Nozaki, Tokiro Numasawa. 2016-02-08. Charged Entanglement Entropy of Local Operators. https://doi.org/10.1103/physrevd.93.105032

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