Spatial multipartite entanglement and localization of entanglement

TL;DR

This paper introduces a model and implementation for generating and analyzing multipartite spatial entanglement in electromagnetic fields, revealing how entanglement can be localized and enhanced between two modes.

Contribution

It presents a simple physical model for multipartite spatial entanglement and demonstrates entanglement localization with an enhancement factor proportional to the square root of the number of mode pairs.

Findings

Entanglement localization enhances entanglement by √N.

The model works for both zero and nonzero phase mismatch.

Spatial entanglement characteristics are thoroughly analyzed.

Abstract

We present a simple model together with its physical implementation which allows one to generate multipartite entanglement between several spatial modes of the electromagnetic field. It is based on parametric down-conversion with N pairs of symmetrically-tilted plane waves serving as a pump. The characteristics of this spatial entanglement are investigated in the cases of zero as well as nonzero phase mismatch. Furthermore, the phenomenon of entanglement localization in just two spatial modes is studied in detail and results in an enhancement of the entanglement by a factor square root of N.