Conformal weights of charged Renyi entropy twist operators for free Dirac fields in arbitrary dimensions

TL;DR

This paper calculates the conformal weights of spherical twist operators with chemical potential for free Dirac fields in any dimension, extending previous scalar field results and revealing phase transitions.

Contribution

It extends the relation between conformal weights and corner coefficients in R'enyi entropy to fermions and uses an image technique for arbitrary dimensions.

Findings

Conformal weights depend on chemical potential and show phase changes.

The conjecture relating conformal weights and corner coefficients is proven for fermions.

Results apply to free Dirac fields in any dimension.

Abstract

The conformal weights of spherical twist operators at non--zero (Euclidean) chemical potential are computed for free Dirac fields in arbitrary dimensions. An image technique, equivalent to replicas, is again used to obtain the $n$--fold cover quantities. The proof of a conjecture made by Bueno, Myers and Witczac--Krempa regarding the relation between the conformal weights and a corner coefficient in the R\'enyi entropy, given before for scalar fields, is extended to the fermion case. The variation of the weights with chemical potential indicates phase changes.