Secret key distillation from shielded two-qubit states

Journal Article · Sat May 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.052320· OSTI ID:21413368

Bae, Joonwoo ^[1]

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1. School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of)

The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.

• OSTI ID: 21413368
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 5 Vol. 81; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
INFORMATION
NOISE
QUANTUM ENTANGLEMENT
QUANTUM INFORMATION
SECURITY