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Title: Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition

Abstract

It is shown that a large class of weak disturbances on macroscopic quantum superpositions can be canceled by a probabilistic reversing operation on the system. We illustrate this for spin systems undergoing an Ising-type interaction with the environment and demonstrate that both the fidelity to the original state and the purity of the amended state can simultaneously be increased by the reversing operation. A possible experimental scheme to implement our scheme is discussed.

Authors:
;  [1];  [2]
  1. Department of Physics, Tokyo Institute of Technology, Tokyo 152-8551 (Japan)
  2. (JST), Saitama 332-0012 (Japan)
Publication Date:
OSTI Identifier:
20982492
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.052323; (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; DISTURBANCES; INTERACTIONS; ISING MODEL; OPERATION; PROBABILISTIC ESTIMATION; PROBABILITY; SPIN

Citation Formats

Terashima, Hiroaki, Ueda, Masahito, and CREST, Japan Science and Technology Corporation. Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.052323.
Terashima, Hiroaki, Ueda, Masahito, & CREST, Japan Science and Technology Corporation. Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition. United States. doi:10.1103/PHYSREVA.75.052323.
Terashima, Hiroaki, Ueda, Masahito, and CREST, Japan Science and Technology Corporation. Tue . "Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition". United States. doi:10.1103/PHYSREVA.75.052323.
@article{osti_20982492,
title = {Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition},
author = {Terashima, Hiroaki and Ueda, Masahito and CREST, Japan Science and Technology Corporation},
abstractNote = {It is shown that a large class of weak disturbances on macroscopic quantum superpositions can be canceled by a probabilistic reversing operation on the system. We illustrate this for spin systems undergoing an Ising-type interaction with the environment and demonstrate that both the fidelity to the original state and the purity of the amended state can simultaneously be increased by the reversing operation. A possible experimental scheme to implement our scheme is discussed.},
doi = {10.1103/PHYSREVA.75.052323},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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