Experiment towards continuous-variable entanglement swapping: Highly correlated four-partite quantum state

Journal Article · Tue Jul 01 04:00:00 EDT 2003 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.68.012319· OSTI ID:20639885

Gloeckl, Oliver; Lorenz, Stefan; Marquardt, Christoph; Heersink, Joel; Brownnutt, Michael; Silberhorn, Christine; Loock, Peter van; Korolkova, Natalia; Leuchs, Gerd ^[1]; Qing, Pan ^[1]

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1. Zentrum fuer Moderne Optik, Physikalisches Institut, Universitaet Erlangen-Nuernberg, Staudtstrasse 7/B2, 91058 Erlangen (Germany)

We present a protocol for performing entanglement swapping with intense pulsed beams. In a first step, the generation of amplitude correlations between two systems that have never interacted directly is demonstrated. This is verified in direct detection with electronic modulation of the detected photocurrents. The measured correlations are better than expected from a classical reconstruction scheme. In an entanglement swapping process, a four-partite entangled state is generated. We prove experimentally that the amplitudes of the four optical modes are quantum correlated 3 dB below shot noise, which is consistent with the presence of genuine four-party entanglement.

• OSTI ID: 20639885
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 1 Vol. 68; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
CORRELATIONS
DETECTION
ENERGY LEVELS
MODULATION
NOISE
OPTICAL MODES
OPTICS
PHOTOCURRENTS
QUANTUM MECHANICS