Quenched entanglement harvesting

TL;DR

This paper investigates how a sudden change in a quantum field's environment affects entanglement harvesting by detectors, supporting the use of quenched systems as analogues for spacetime phenomena like the Unruh effect.

Contribution

It analyzes entanglement harvesting in a (1+1)-D continuum spacetime with a quench, providing numerical evidence of similarities to Rindler spacetime and supporting experimental analogues.

Findings

Harvested entanglement shows qualitative similarity to Rindler spacetime.

Small variations occur when the energy pulse crosses the detectors.

Results support experimental implementation of quenched spacetime analogues.

Abstract

Ultracold fermionic atoms in an optical lattice, with a sudden position-dependent change (a quench) in the effective dispersion relation, have been proposed by Rodr\'iguez-Laguna et al as an analogue spacetime test of the Unruh effect. We provide new support for this analogue by analysing the entanglement of a scalar field in a (1 + 1)-dimensional continuum spacetime with a similar quench, and the harvesting of this entanglement by a pair of Unruh-DeWitt detectors. We present numerical evidence that the concurrence and mutual information harvested by the detectors are qualitatively similar to those in Rindler spacetime, but they exhibit a small yet noticeable variation when the energy pulse created by the quench crosses the detectors. These findings provide further motivation to implement the experimental proposal of Rodr\'iguez-Laguna et al.