Robustness of multiqubit entanglement in the independent decoherence model

Journal Article · Sat Oct 15 04:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.72.042339· OSTI ID:20718732

Bandyopadhyay, Somshubhro ^[1]; Lidar, Daniel A ^[1]

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1. Chemical Physics Theory Group, Chemistry Department, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, ON M5S 3H6 (Canada)

We study the robustness of the Greenberger-Horne-Zeilinger ('cat') class of multipartite states under decoherence. The noise model is described by a general completely positive map for qubits independently coupled to the environment. In particular, the robustness of N-party entanglement is studied in the large N limit when (a) the number of spatially separated subsystems is fixed but the size of each subsystem becomes large and (b) the size of the subsystems is fixed while their number becomes arbitrarily large. We obtain conditions for entanglement in these two cases. Among our other results, we show that the parity of an entangled state (i.e., whether it contains an even or odd number of qubits) can lead to qualitatively different robustness of entanglement under certain conditions.

• OSTI ID: 20718732
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 72; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ENERGY LEVELS
NOISE
PARITY
QUANTUM COMPUTERS
QUANTUM DECOHERENCE
QUANTUM ENTANGLEMENT
QUBITS