English

R\'enyi entropy and negativity for massless Dirac fermions at conformal interfaces and junctions

High Energy Physics - Theory 2022-09-21 v1 Statistical Mechanics

Abstract

We investigate the ground state of a (1+1)-dimensional conformal field theory built with MM species of massless free Dirac fermions coupled at one boundary point via a conformal junction/interface. Each CFT represents a wire of finite length LL. We develop a systematic strategy to compute the R\'enyi entropies for a generic bipartition between the wires and the entanglement negativity between two non-complementary sets of wires. Both these entanglement measures turn out to grow logarithmically with LL with an exactly calculated universal prefactor depending on the details of the junction and of the bipartition. These analytic predictions are tested numerically for junctions of free Fermi gases, finding perfect agreement.

Keywords

Cite

@article{arxiv.2205.04722,
  title  = {R\'enyi entropy and negativity for massless Dirac fermions at conformal interfaces and junctions},
  author = {Luca Capizzi and Sara Murciano and Pasquale Calabrese},
  journal= {arXiv preprint arXiv:2205.04722},
  year   = {2022}
}