Action scales for quantum decoherence and their relation to structures in phase space
Abstract
A characteristic action {delta}S is defined whose magnitude determines some properties of the expectation value of a general quantum displacement operator. These properties are related to the capability of a given environmental ''monitoring'' system to induce decoherence in quantum systems coupled to it. We show that the scale for effective decoherence is given by {delta}S{approx_equal}({Dirac_h}/2{pi}). We relate this characteristic action with a complementary quantity, {delta}Z, and analyze their connection with the main features of the pattern of structures developed by the environmental state in different phase space representations. The relevance of the {delta}Saction scale is illustrated using both a model quantum system solved numerically and a set of model quantum systems for which analytical expressions for the timeaveraged expectation value of the displacement operator are obtained explicitly.
 Authors:
 Departamento de Fisica Fundamental y Experimental, Electronica y Sistemas, Universidad de La Laguna, La Laguna 38203, Tenerife (Spain)
 Departamento de Fisica Fundamental II, Universidad de La Laguna, La Laguna 38203, Tenerife (Spain)
 Publication Date:
 OSTI Identifier:
 20641106
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 69; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.69.052111; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; CHAOS THEORY; EXPECTATION VALUE; PHASE SPACE; QUANTUM MECHANICS; QUANTUM OPERATORS
Citation Formats
Alonso, Daniel, Brouard, S., Palao, Jose P., and Mayato, R. Sala. Action scales for quantum decoherence and their relation to structures in phase space. United States: N. p., 2004.
Web. doi:10.1103/PhysRevA.69.052111.
Alonso, Daniel, Brouard, S., Palao, Jose P., & Mayato, R. Sala. Action scales for quantum decoherence and their relation to structures in phase space. United States. doi:10.1103/PhysRevA.69.052111.
Alonso, Daniel, Brouard, S., Palao, Jose P., and Mayato, R. Sala. Sat .
"Action scales for quantum decoherence and their relation to structures in phase space". United States.
doi:10.1103/PhysRevA.69.052111.
@article{osti_20641106,
title = {Action scales for quantum decoherence and their relation to structures in phase space},
author = {Alonso, Daniel and Brouard, S. and Palao, Jose P. and Mayato, R. Sala},
abstractNote = {A characteristic action {delta}S is defined whose magnitude determines some properties of the expectation value of a general quantum displacement operator. These properties are related to the capability of a given environmental ''monitoring'' system to induce decoherence in quantum systems coupled to it. We show that the scale for effective decoherence is given by {delta}S{approx_equal}({Dirac_h}/2{pi}). We relate this characteristic action with a complementary quantity, {delta}Z, and analyze their connection with the main features of the pattern of structures developed by the environmental state in different phase space representations. The relevance of the {delta}Saction scale is illustrated using both a model quantum system solved numerically and a set of model quantum systems for which analytical expressions for the timeaveraged expectation value of the displacement operator are obtained explicitly.},
doi = {10.1103/PhysRevA.69.052111},
journal = {Physical Review. A},
number = 5,
volume = 69,
place = {United States},
year = {Sat May 01 00:00:00 EDT 2004},
month = {Sat May 01 00:00:00 EDT 2004}
}

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