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Title: Decoherence modes of entangled qubits within neutron interferometry

Abstract

We study two different decoherence modes for entangled qubits by considering a Liouville-von Neumann master equation. Mode A is determined by projection operators onto the eigenstates of the Hamiltonian and mode B by projectors onto rotated states. We present solutions for general and for Bell diagonal states and calculate for the latter the mixedness and the amount of entanglement given by the concurrence. We propose a realization of the decoherence modes within neutron interferometry by applying fluctuating magnetic fields. An experimental test of the Kraus operator decomposition describing the evolution of the system for each mode is presented.

Authors:
;  [1];  [2];  [3]
  1. Institute for Theoretical Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna (Austria)
  2. Atominstitut der Oesterreichischen Universitaeten, Stadionallee 2, 1020 Vienna (Austria)
  3. (Japan)
Publication Date:
OSTI Identifier:
20974513
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.022111; (c) 2006 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; BELL THEOREM; EIGENSTATES; EQUATIONS; EVOLUTION; HAMILTONIANS; INTERFEROMETRY; MAGNETIC FIELDS; MATHEMATICAL SOLUTIONS; NEUTRONS; PARTICLES; QUANTUM COMPUTERS; QUANTUM DECOHERENCE; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; QUBITS

Citation Formats

Bertlmann, Reinhold A., Durstberger, Katharina, Hasegawa, Yuji, and PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama. Decoherence modes of entangled qubits within neutron interferometry. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.022111.
Bertlmann, Reinhold A., Durstberger, Katharina, Hasegawa, Yuji, & PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama. Decoherence modes of entangled qubits within neutron interferometry. United States. doi:10.1103/PHYSREVA.73.022111.
Bertlmann, Reinhold A., Durstberger, Katharina, Hasegawa, Yuji, and PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama. Wed . "Decoherence modes of entangled qubits within neutron interferometry". United States. doi:10.1103/PHYSREVA.73.022111.
@article{osti_20974513,
title = {Decoherence modes of entangled qubits within neutron interferometry},
author = {Bertlmann, Reinhold A. and Durstberger, Katharina and Hasegawa, Yuji and PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama},
abstractNote = {We study two different decoherence modes for entangled qubits by considering a Liouville-von Neumann master equation. Mode A is determined by projection operators onto the eigenstates of the Hamiltonian and mode B by projectors onto rotated states. We present solutions for general and for Bell diagonal states and calculate for the latter the mixedness and the amount of entanglement given by the concurrence. We propose a realization of the decoherence modes within neutron interferometry by applying fluctuating magnetic fields. An experimental test of the Kraus operator decomposition describing the evolution of the system for each mode is presented.},
doi = {10.1103/PHYSREVA.73.022111},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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