Charged Entanglement Entropy of Local Operators

TL;DR

This paper investigates how charged Renyi entanglement entropies evolve after local operator excitations across various theories and dimensions, revealing their interpretation via charged quasiparticles and their utility in probing specific charge sectors.

Contribution

It provides a comprehensive analysis of charged Renyi entropies in 2d CFT, free fermionic theories, and holography, highlighting their dependence on charge, chemical potential, and dimension, and their interpretation in terms of charged quasiparticles.

Findings

Charged Renyi entropies can be interpreted through charged quasiparticles.

Tuning chemical potential allows extraction of entanglement in specific charge sectors.

Excesses of charged entanglement entropy depend on charge, chemical potential, and spacetime dimension.

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.