Effects of spectral entanglement in polarization-entanglement swapping and type-I fusion gates

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.77.022312· OSTI ID:931040

Humble, Travis S ^[1]; Grice, Warren P ^[1]

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1. ORNL

We examine how spectral entanglement in polarization-entangled photon states generated from bulk-crystal, spontaneous parametric down-conversion affects the success of entanglement swapping and type-I fusion gates. We quantify the success of the entanglement swapping and fusion gates by calculating the bipartite concurrence and residual tangle, respectively, in terms of the joint spectral probability amplitudes of the initial broad-bandwidth polarization-entangled states. We find that both polarization-entanglement measures depend strongly on the initial spectral entanglement, as well as on the configuration of the independent sources. Specifically, when spectral differences correlate with polarization, the optimal source configuration is different for the two protocols. We conclude that this distinction is founded in how the underlying Bell-state measurement and quantum-erasure techniques respond differently to distinguishing spectral information.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: Work for Others (WFO)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 931040
• Journal Information: Physical Review A, Vol. 77, Issue 2; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
CONFIGURATION
PHOTONS
POLARIZATION
PROBABILITY
QUANTUM ENTANGLEMENT
quantum information science
quantum computing
quantum repeater