Atom cooling by nonadiabatic expansion
Abstract
Motivated by the recent discovery that a reflecting wall moving with a squarerootintime trajectory behaves as a universal stopper of classical particles regardless of their initial velocities, we compare linearintime and squarerootintime expansions of a box to achieve efficient atom cooling. For the quantum singleatom wave functions studied the squarerootintime expansion presents important advantages: asymptotically it leads to zero average energy whereas any linearintime (constant boxwall velocity) expansion leaves a nonzero residual energy, except in the limit of an infinitely slow expansion. For finite final times and box lengths we set a number of bounds and cooling principles which again confirm the superior performance of the squarerootintime expansion, even more clearly for increasing excitation of the initial state. Breakdown of adiabaticity is generally fatal for cooling with the linear expansion but not so with the squarerootintime expansion.
 Authors:
 Departamento de QuimicaFisica, UPVEHU, Apdo 644, 48080 Bilbao (Spain)
 (China)
 Institute for Mathematical Sciences, Imperial College London, 53 Princes Gate, SW7 2PG London (United Kingdom)
 (United Kingdom)
 Institut fuer Theoretische Physik, Leibniz Universitaet Hannover, Appelstrasse 2, 30167 Hannover (Germany)
 Publication Date:
 OSTI Identifier:
 21352388
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 80; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.80.063421; (c) 2009 The American Physical Society
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; COMPARATIVE EVALUATIONS; COOLING; EXCITATION; EXPANSION; RUBIDIUM; WAVE FUNCTIONS; ALKALI METALS; ELEMENTS; ENERGYLEVEL TRANSITIONS; EVALUATION; FUNCTIONS; METALS
Citation Formats
Chen Xi, Department of Physics, Shanghai University, 200444 Shanghai, Muga, J. G., Campo, A. del, QOLS, Blackett Laboratory, Imperial College London, Prince Consort Road, SW7 2BW London, and Ruschhaupt, A. Atom cooling by nonadiabatic expansion. United States: N. p., 2009.
Web. doi:10.1103/PHYSREVA.80.063421.
Chen Xi, Department of Physics, Shanghai University, 200444 Shanghai, Muga, J. G., Campo, A. del, QOLS, Blackett Laboratory, Imperial College London, Prince Consort Road, SW7 2BW London, & Ruschhaupt, A. Atom cooling by nonadiabatic expansion. United States. doi:10.1103/PHYSREVA.80.063421.
Chen Xi, Department of Physics, Shanghai University, 200444 Shanghai, Muga, J. G., Campo, A. del, QOLS, Blackett Laboratory, Imperial College London, Prince Consort Road, SW7 2BW London, and Ruschhaupt, A. 2009.
"Atom cooling by nonadiabatic expansion". United States.
doi:10.1103/PHYSREVA.80.063421.
@article{osti_21352388,
title = {Atom cooling by nonadiabatic expansion},
author = {Chen Xi and Department of Physics, Shanghai University, 200444 Shanghai and Muga, J. G. and Campo, A. del and QOLS, Blackett Laboratory, Imperial College London, Prince Consort Road, SW7 2BW London and Ruschhaupt, A.},
abstractNote = {Motivated by the recent discovery that a reflecting wall moving with a squarerootintime trajectory behaves as a universal stopper of classical particles regardless of their initial velocities, we compare linearintime and squarerootintime expansions of a box to achieve efficient atom cooling. For the quantum singleatom wave functions studied the squarerootintime expansion presents important advantages: asymptotically it leads to zero average energy whereas any linearintime (constant boxwall velocity) expansion leaves a nonzero residual energy, except in the limit of an infinitely slow expansion. For finite final times and box lengths we set a number of bounds and cooling principles which again confirm the superior performance of the squarerootintime expansion, even more clearly for increasing excitation of the initial state. Breakdown of adiabaticity is generally fatal for cooling with the linear expansion but not so with the squarerootintime expansion.},
doi = {10.1103/PHYSREVA.80.063421},
journal = {Physical Review. A},
number = 6,
volume = 80,
place = {United States},
year = 2009,
month =
}

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