Experimental Observation of Four-Photon Entangled Dicke State with High Fidelity

2006/06/28 by Nikolai Kiesel, Ch. Schmid, Christian Schmid +5 · 7 citations
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #quant-ph

paper · pdf · doi:10.1103/physrevlett.98.063604

published as Phys. Rev. Lett. 98, 063604 (2007) · 5 pages, 3 figures, submitted

arxiv created 2006/06/28 · openalex publication_date 2007/02/07 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We present the experimental observation of the symmetric four-photon entangled Dicke state with two excitations |D₄;(2). A simple experimental setup allowed quantum state tomography yielding a fidelity as high as 0.844+/-0.008. We study the entanglement persistency of the state using novel witness operators and focus on the demonstration of a remarkable property: depending on the orientation of a measurement on one photon, the remaining three photons are projected into both inequivalent classes of genuine tripartite entanglement, the Greenberger-Horne-Zeilinger and W class. Furthermore, we discuss possible applications of |D₄;(2) in quantum communication.

Citations

• Three qubits can be entangled in two inequivalent ways
• Characterizing the entanglement of symmetric many-particle spin-12systems
• Entanglement detection in the stabilizer formalism
• Scalable multi-particle entanglement of trapped ions

Cited by

• Multiqubit entanglement engineering via projective measurements
• Robust creation of arbitrary-sized Dicke states of trapped ions by global addressing
• Generation of Symmetric Dicke States of Remote Qubits with Linear Optics
• Spin squeezing and entanglement
• Practical methods for witnessing genuine multi-qubit entanglement in the vicinity of symmetric states
• Toolbox for entanglement detection and fidelity estimation
• Quantum Correlation without Classical Correlations