Experimental entanglement of a six-photon symmetric Dicke state

TL;DR

This paper reports the experimental creation and analysis of a six-photon symmetric Dicke state, demonstrating high fidelity, genuine six-photon entanglement, and notable properties like entanglement persistency and state conversion capabilities.

Contribution

The study presents the first experimental realization of a six-photon symmetric Dicke state with detailed characterization and analysis of its unique entanglement properties.

Findings

Fidelity of 0.654±0.024 achieved

Genuine six-photon entanglement confirmed

State exhibits high entanglement persistency

Abstract

We report on the experimental observation and characterization of a six-photon entangled Dicke state. We obtain a fidelity as high as 0.654$\pm$0.024 and prove genuine six-photon entanglement by, amongst others, a two-setting witness yielding -0.422$\pm$0.148. This state has remarkable properties; e.g., it allows obtaining inequivalent entangled states of a lower qubit number via projective measurements, and it possesses a high entanglement persistency against qubit loss. We characterize the properties of the six-photon Dicke state experimentally by detecting and analyzing the entanglement of a variety of multipartite entangled states.