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Title: Entanglement purification with double selection

Abstract

We investigate an entanglement purification protocol with double-selection process, which works under imperfect local operations. Compared with the usual protocol with single selection, this double-selection method has higher noise thresholds for the local operations and quantum communication channels and achieves higher fidelity of purified states. It also provides a yield comparable to that of the usual protocol with single selection. We discuss on general grounds how some of the errors which are introduced by local operations are left as intrinsically undetectable. The undetectable errors place a general upper bound on the purification fidelity. The double selection is a simple method to remove all the detectable errors in the first order, so that the upper bound on the fidelity is achieved in the low-noise regime. The double selection is further applied to purification of multipartite entanglement such as two-colorable graph states.

Authors:
;  [1]
  1. Department of Nuclear Engineering, Kyoto University, Kyoto 606-8501 (Japan)
Publication Date:
OSTI Identifier:
21316361
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 80; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.80.042308; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMMUNICATIONS; ERRORS; NOISE; QUANTUM ENTANGLEMENT; YIELDS

Citation Formats

Fujii, Keisuke, and Yamamoto, Katsuji. Entanglement purification with double selection. United States: N. p., 2009. Web. doi:10.1103/PHYSREVA.80.042308.
Fujii, Keisuke, & Yamamoto, Katsuji. Entanglement purification with double selection. United States. doi:10.1103/PHYSREVA.80.042308.
Fujii, Keisuke, and Yamamoto, Katsuji. 2009. "Entanglement purification with double selection". United States. doi:10.1103/PHYSREVA.80.042308.
@article{osti_21316361,
title = {Entanglement purification with double selection},
author = {Fujii, Keisuke and Yamamoto, Katsuji},
abstractNote = {We investigate an entanglement purification protocol with double-selection process, which works under imperfect local operations. Compared with the usual protocol with single selection, this double-selection method has higher noise thresholds for the local operations and quantum communication channels and achieves higher fidelity of purified states. It also provides a yield comparable to that of the usual protocol with single selection. We discuss on general grounds how some of the errors which are introduced by local operations are left as intrinsically undetectable. The undetectable errors place a general upper bound on the purification fidelity. The double selection is a simple method to remove all the detectable errors in the first order, so that the upper bound on the fidelity is achieved in the low-noise regime. The double selection is further applied to purification of multipartite entanglement such as two-colorable graph states.},
doi = {10.1103/PHYSREVA.80.042308},
journal = {Physical Review. A},
number = 4,
volume = 80,
place = {United States},
year = 2009,
month =
}
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