Entanglement swapping with PDC sources

TL;DR

This paper demonstrates that entanglement swapping can be validated without distinguishing single from two-photon events, and proposes a modified experiment revealing more phenomena.

Contribution

It shows that local realistic explanations are not ruled out by current entanglement swapping experiments and introduces a modified setup for richer phenomena.

Findings

Distinguishing detection events is not necessary for entanglement swapping validation.

Proposed modification reveals additional interesting phenomena.

Supports non-local interpretations beyond current experimental limitations.

Abstract

We show that the possibility of distinguishing between single and two photon detection events is not a necessary requirement for the proof that recent operational realization of entanglement swapping cannot find a local realistic description. We propose a simple modification of the experiment, which gives a richer set of interesting phenomena.