Entangling Bosons through Particle Indistinguishability and Spatial Overlap

TL;DR

This paper investigates how particle indistinguishability and spatial overlap influence entanglement between two bosons, combining theoretical analysis with experimental verification in a photonic system.

Contribution

It provides the first quantitative analysis of the combined effects of indistinguishability and spatial overlap on bosonic entanglement, supported by experimental data.

Findings

Entanglement increases monotonically with both particle indistinguishability and spatial overlap.

Theoretical predictions are confirmed through photonic experiments.

Results offer insights into quantum networks with identical particles.

Abstract

Particle identity and entanglement are two fundamental quantum properties that work as major resources for various quantum information tasks. However, it is still a challenging problem to understand the correlation of the two properties in the same system. While recent theoretical studies have shown that the spatial overlap between identical particles is necessary for nontrivial entanglement, the exact role of particle indistinguishability in the entanglement of identical particles has never been analyzed quantitatively before. Here, we theoretically and experimentally investigate the behavior of entanglement between two bosons as spatial overlap and indistinguishability simultaneously vary. The theoretical computation of entanglement for generic two bosons with pseudospins is verified experimentally in a photonic system. Our results show that the amount of entanglement is a monotonically increasing function of both quantities. We expect that our work provides an insight into deciphering the role of the entanglement in quantum networks that consist of identical particles.