Extraction of genuine tripartite entanglement from the vacuum

TL;DR

This paper demonstrates how three quantum detectors can extract genuine tripartite entanglement directly from the vacuum state of a quantum field in a cavity, using an exact oscillator-detector model.

Contribution

It introduces an exact, non-perturbative model for entanglement extraction from the vacuum and compares entanglement extraction efficiency between periodic and Dirichlet boundary conditions.

Findings

Tripartite entanglement extraction is easier than bipartite.

Extraction is more efficient in a periodic cavity than with Dirichlet boundaries.

The model avoids perturbation theory, enabling exact analysis.

Abstract

We demonstrate and characterize the extraction of genuine tripartite entanglement from the vacuum of a periodic cavity field. That is, three probe quantum systems (detectors) can become both bipartitely and tripartitely entangled without coming into causal contact, by means of interaction with a common quantum field. We do this by using an oscillator-detector model that forgoes the need for perturbation theory and which instead is solved exactly. We find that the extraction of tripartite entanglement is considerably easier than that of bipartite. As a secondary result, we also compare a periodic cavity with one that has Dirichlet boundary conditions. We find that the extraction of both bipartite and tripartite entanglement is more easily achieved using the former case.