Protecting quantum coherence of twolevel atoms from vacuum fluctuations of electromagnetic field
Abstract
In the framework of open quantum systems, we study the dynamics of a static polarizable twolevel atom interacting with a bath of fluctuating vacuum electromagnetic field and explore under which conditions the coherence of the open quantum system is unaffected by the environment. For both a singlequbit and twoqubit systems, we find that the quantum coherence cannot be protected from noise when the atom interacts with a nonboundary electromagnetic field. However, with the presence of a boundary, the dynamical conditions for the insusceptible of quantum coherence are fulfilled only when the atom is close to the boundary and is transversely polarizable. Otherwise, the quantum coherence can only be protected in some degree in other polarizable direction.  Highlights: •We study the dynamics of a twolevel atom interacting with a bath of fluctuating vacuum electromagnetic field. •For both a single and twoqubit systems, the quantum coherence cannot be protected from noise without a boundary. •The insusceptible of the quantum coherence can be fulfilled only when the atom is close to the boundary and is transversely polarizable. •Otherwise, the quantum coherence can only be protected in some degree in other polarizable direction.
 Authors:
 Publication Date:
 OSTI Identifier:
 22560304
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Annals of Physics; Journal Volume: 366; Journal Issue: Complete; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; ELECTROMAGNETIC FIELDS; ENERGY LEVELS; FLUCTUATIONS; NOISE; QUANTUM DECOHERENCE; QUANTUM SYSTEMS; QUBITS
Citation Formats
Liu, Xiaobao, Tian, Zehua, Wang, Jieci, and Jing, Jiliang, Email: jljing@hunnu.edu.cn. Protecting quantum coherence of twolevel atoms from vacuum fluctuations of electromagnetic field. United States: N. p., 2016.
Web. doi:10.1016/J.AOP.2015.12.010.
Liu, Xiaobao, Tian, Zehua, Wang, Jieci, & Jing, Jiliang, Email: jljing@hunnu.edu.cn. Protecting quantum coherence of twolevel atoms from vacuum fluctuations of electromagnetic field. United States. doi:10.1016/J.AOP.2015.12.010.
Liu, Xiaobao, Tian, Zehua, Wang, Jieci, and Jing, Jiliang, Email: jljing@hunnu.edu.cn. 2016.
"Protecting quantum coherence of twolevel atoms from vacuum fluctuations of electromagnetic field". United States.
doi:10.1016/J.AOP.2015.12.010.
@article{osti_22560304,
title = {Protecting quantum coherence of twolevel atoms from vacuum fluctuations of electromagnetic field},
author = {Liu, Xiaobao and Tian, Zehua and Wang, Jieci and Jing, Jiliang, Email: jljing@hunnu.edu.cn},
abstractNote = {In the framework of open quantum systems, we study the dynamics of a static polarizable twolevel atom interacting with a bath of fluctuating vacuum electromagnetic field and explore under which conditions the coherence of the open quantum system is unaffected by the environment. For both a singlequbit and twoqubit systems, we find that the quantum coherence cannot be protected from noise when the atom interacts with a nonboundary electromagnetic field. However, with the presence of a boundary, the dynamical conditions for the insusceptible of quantum coherence are fulfilled only when the atom is close to the boundary and is transversely polarizable. Otherwise, the quantum coherence can only be protected in some degree in other polarizable direction.  Highlights: •We study the dynamics of a twolevel atom interacting with a bath of fluctuating vacuum electromagnetic field. •For both a single and twoqubit systems, the quantum coherence cannot be protected from noise without a boundary. •The insusceptible of the quantum coherence can be fulfilled only when the atom is close to the boundary and is transversely polarizable. •Otherwise, the quantum coherence can only be protected in some degree in other polarizable direction.},
doi = {10.1016/J.AOP.2015.12.010},
journal = {Annals of Physics},
number = Complete,
volume = 366,
place = {United States},
year = 2016,
month = 3
}

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