Reflected entropy in BCFTs on a black hole background

TL;DR

This paper calculates the reflected entropy for bipartite states in BCFTs on a black hole background, confirming holographic duality through bulk geometry analysis and exploring related entanglement properties.

Contribution

It provides the first holographic computation of reflected entropy in BCFTs on a black hole background, linking boundary calculations with bulk AdS geometries.

Findings

Reflected entropy matches entanglement wedge cross section in the bulk

Verified holographic duality for BCFTs in black hole backgrounds

Analyzed Page curves and Markov gap for reflected entropy

Abstract

We obtain the reflected entropy for bipartite mixed state configurations involving two disjoint and adjacent subsystems in two dimensional boundary conformal field theories (BCFT$_2$s) in a black hole background. The bulk dual is described by an AdS$_3$ black string geometry truncated by a Karch-Randall brane. The entanglement wedge cross section computed for this geometry matches with the reflected entropy obtained for the BCFT$_2$ verifying the holographic duality. In this context, we also obtain the analogues of the Page curves for the reflected entropy and investigate the behaviour of the Markov gap.