Quantum dynamics of localized excitations in a symmetric trimer molecule
Abstract
We study the time evolution of localized (local bond) excitations in a symmetric quantum trimer molecule. We relate the dynamical properties of localized excitations such as their spectral intensity and their temporal evolution (survival probability and tunneling of bosons) to their degree of overlap with quantum tunneling pair states. We report on the existence of degeneracy points in the trimer eigenvalue spectrum for specific values of parameters due to avoided crossings between tunneling pair states and additional states. The tunneling of localized excitations which overlap with these degenerate states is suppressed at all times. As a result local bond excitations may be strongly localized forever, similar to their classical counterparts.
 Authors:
 MaxPlanckInstitut fuer Physik komplexer Systeme, Noethnitzer Strasse 38, 01187 Dresden (Germany)
 Publication Date:
 OSTI Identifier:
 20974588
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.022717; (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; BOSONS; EIGENVALUES; EXCITATION; EXCITED STATES; MOLECULES; PROBABILITY; SPECTRA; TUNNEL EFFECT
Citation Formats
Pinto, R. A., and Flach, S. Quantum dynamics of localized excitations in a symmetric trimer molecule. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.022717.
Pinto, R. A., & Flach, S. Quantum dynamics of localized excitations in a symmetric trimer molecule. United States. doi:10.1103/PHYSREVA.73.022717.
Pinto, R. A., and Flach, S. Wed .
"Quantum dynamics of localized excitations in a symmetric trimer molecule". United States.
doi:10.1103/PHYSREVA.73.022717.
@article{osti_20974588,
title = {Quantum dynamics of localized excitations in a symmetric trimer molecule},
author = {Pinto, R. A. and Flach, S.},
abstractNote = {We study the time evolution of localized (local bond) excitations in a symmetric quantum trimer molecule. We relate the dynamical properties of localized excitations such as their spectral intensity and their temporal evolution (survival probability and tunneling of bosons) to their degree of overlap with quantum tunneling pair states. We report on the existence of degeneracy points in the trimer eigenvalue spectrum for specific values of parameters due to avoided crossings between tunneling pair states and additional states. The tunneling of localized excitations which overlap with these degenerate states is suppressed at all times. As a result local bond excitations may be strongly localized forever, similar to their classical counterparts.},
doi = {10.1103/PHYSREVA.73.022717},
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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