Current behavior of a quantum Hamiltonian ratchet in resonance
Abstract
We investigate the ratchet current that appears in a kicked Hamiltonian system when the period of the kicks corresponds to the regime of quantum resonance. In the classical analog, a spatialtemporal symmetry should be broken to obtain a net directed current. It was recently discovered that in quantum resonance the temporal symmetry can be kept, and we prove that breaking the spatial symmetry is a necessary condition to find this effect. Moreover, we show numerically and analytically how the direction of the motion is dramatically influenced by the strength of the kicking potential and the value of the period. By increasing the strength of the interaction this direction changes periodically, providing us with unexpected source of current reversals in this quantum model. These reversals depend on the kicking period also, though this behavior is theoretically more difficult to analyze. Finally, we generalize the discussion to the case of a nonuniform initial condition.
 Authors:
 Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542 (Singapore)
 Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250, 1429 Buenos Aires (Argentina)
 (Singapore)
 (China)
 Publication Date:
 OSTI Identifier:
 21072266
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevE.75.011102; (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; CURRENTS; HAMILTONIANS; PERIODICITY; POTENTIALS; QUANTUM MECHANICS; RESONANCE; SYMMETRY
Citation Formats
Poletti, Dario, Carlo, Gabriel G., Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542, Li Baowen, Laboratory of Modern Acoustics and Institute of Acoustics, Nanjing University, 210093, and Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117597. Current behavior of a quantum Hamiltonian ratchet in resonance. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVE.75.011102.
Poletti, Dario, Carlo, Gabriel G., Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542, Li Baowen, Laboratory of Modern Acoustics and Institute of Acoustics, Nanjing University, 210093, & Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117597. Current behavior of a quantum Hamiltonian ratchet in resonance. United States. doi:10.1103/PHYSREVE.75.011102.
Poletti, Dario, Carlo, Gabriel G., Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542, Li Baowen, Laboratory of Modern Acoustics and Institute of Acoustics, Nanjing University, 210093, and Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117597. Mon .
"Current behavior of a quantum Hamiltonian ratchet in resonance". United States.
doi:10.1103/PHYSREVE.75.011102.
@article{osti_21072266,
title = {Current behavior of a quantum Hamiltonian ratchet in resonance},
author = {Poletti, Dario and Carlo, Gabriel G. and Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542 and Li Baowen and Laboratory of Modern Acoustics and Institute of Acoustics, Nanjing University, 210093 and Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117597},
abstractNote = {We investigate the ratchet current that appears in a kicked Hamiltonian system when the period of the kicks corresponds to the regime of quantum resonance. In the classical analog, a spatialtemporal symmetry should be broken to obtain a net directed current. It was recently discovered that in quantum resonance the temporal symmetry can be kept, and we prove that breaking the spatial symmetry is a necessary condition to find this effect. Moreover, we show numerically and analytically how the direction of the motion is dramatically influenced by the strength of the kicking potential and the value of the period. By increasing the strength of the interaction this direction changes periodically, providing us with unexpected source of current reversals in this quantum model. These reversals depend on the kicking period also, though this behavior is theoretically more difficult to analyze. Finally, we generalize the discussion to the case of a nonuniform initial condition.},
doi = {10.1103/PHYSREVE.75.011102},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}

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