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Title: Selective entanglement breaking

Abstract

We discuss the cases where local decoherence selectively degrades one type of entanglement more than other types. A typical case is called state ordering change, in which two input states with different amounts of entanglement undergoes a local decoherence and the state with the larger entanglement results in an output state with less entanglement than the other output state. We are also interested in a special case where the state with the larger entanglement evolves to a separable state while the other output state is still entangled, which we call selective entanglement breaking. For three-level or larger systems, it is easy to find examples of the state ordering change and the selective entanglement breaking, but for two-level systems it is not trivial whether such situations exist. We present a general strategy to construct examples of two-qubit states exhibiting the selective entanglement breaking regardless of entanglement measure. We also give a more striking example of the selective entanglement breaking in which the less entangled input state has only an infinitesimal amount of entanglement.

Authors:
; ;  [1];  [2]; ;  [1];  [2];  [2]
  1. Division of Materials Physics, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20982253
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032307; (c) 2007 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; QUANTUM COMPUTERS; QUANTUM DECOHERENCE; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; QUBITS

Citation Formats

Kinoshita, Yuma, Namiki, Ryo, Yamamoto, Takashi, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, Koashi, Masato, Imoto, Nobuyuki, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, and SORST Research Team for Interacting Carrier Electronics, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012. Selective entanglement breaking. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032307.
Kinoshita, Yuma, Namiki, Ryo, Yamamoto, Takashi, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, Koashi, Masato, Imoto, Nobuyuki, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, & SORST Research Team for Interacting Carrier Electronics, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012. Selective entanglement breaking. United States. doi:10.1103/PHYSREVA.75.032307.
Kinoshita, Yuma, Namiki, Ryo, Yamamoto, Takashi, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, Koashi, Masato, Imoto, Nobuyuki, CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012, and SORST Research Team for Interacting Carrier Electronics, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012. Thu . "Selective entanglement breaking". United States. doi:10.1103/PHYSREVA.75.032307.
@article{osti_20982253,
title = {Selective entanglement breaking},
author = {Kinoshita, Yuma and Namiki, Ryo and Yamamoto, Takashi and CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012 and Koashi, Masato and Imoto, Nobuyuki and CREST Research Team for Photonic Quantum Information, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012 and SORST Research Team for Interacting Carrier Electronics, 4-1-8 Honmachi, Kawaguchi, Saitama 331-0012},
abstractNote = {We discuss the cases where local decoherence selectively degrades one type of entanglement more than other types. A typical case is called state ordering change, in which two input states with different amounts of entanglement undergoes a local decoherence and the state with the larger entanglement results in an output state with less entanglement than the other output state. We are also interested in a special case where the state with the larger entanglement evolves to a separable state while the other output state is still entangled, which we call selective entanglement breaking. For three-level or larger systems, it is easy to find examples of the state ordering change and the selective entanglement breaking, but for two-level systems it is not trivial whether such situations exist. We present a general strategy to construct examples of two-qubit states exhibiting the selective entanglement breaking regardless of entanglement measure. We also give a more striking example of the selective entanglement breaking in which the less entangled input state has only an infinitesimal amount of entanglement.},
doi = {10.1103/PHYSREVA.75.032307},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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