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Title: The role of interactions, tunneling, and harmonic confinement on the adiabatic loading of bosons in an optical lattice

Abstract

We calculate entropy-temperature curves for interacting bosons in unit filled optical lattices for both homogeneous and harmonically trapped situations, and use them to understand how adiabatic changes in the lattice depth affect the temperature of the system. In a translationally invariant lattice, the zero tunneling limit facilitates a rather detailed analytic description. Unlike the noninteracting bosonic system which is always cooled upon adiabatic loading for low enough initial temperature, the change in the excitation spectrum induced by interactions can lead to heating. Finite tunneling helps to reduce this heating. Finally, we study the spatially inhomogeneous system confined in a parabolic potential and show that the presence of the trap can significantly reduce the final available temperature, due to the nonvanishing superfluid component at the edge of the cloud which is present in trapped systems.

Authors:
 [1];  [2];  [1];  [3];  [1]
  1. National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
  2. (United States)
  3. (Austria)
Publication Date:
OSTI Identifier:
20974624
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.023608; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSONS; CONFINEMENT; COOLING; DIAGRAMS; ENTROPY; EXCITATION; HEATING; INTERACTING BOSON MODEL; INTERACTIONS; POTENTIALS; SPECTRA; SUPERFLUIDITY; TRAPPING; TRAPS; TUNNEL EFFECT

Citation Formats

Rey, Ana Maria, Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center of Astrophysics, Cambridge, Maryland 02138, Pupillo, Guido, Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck, and Porto, J. V.. The role of interactions, tunneling, and harmonic confinement on the adiabatic loading of bosons in an optical lattice. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.023608.
Rey, Ana Maria, Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center of Astrophysics, Cambridge, Maryland 02138, Pupillo, Guido, Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck, & Porto, J. V.. The role of interactions, tunneling, and harmonic confinement on the adiabatic loading of bosons in an optical lattice. United States. doi:10.1103/PHYSREVA.73.023608.
Rey, Ana Maria, Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center of Astrophysics, Cambridge, Maryland 02138, Pupillo, Guido, Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck, and Porto, J. V.. Wed . "The role of interactions, tunneling, and harmonic confinement on the adiabatic loading of bosons in an optical lattice". United States. doi:10.1103/PHYSREVA.73.023608.
@article{osti_20974624,
title = {The role of interactions, tunneling, and harmonic confinement on the adiabatic loading of bosons in an optical lattice},
author = {Rey, Ana Maria and Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center of Astrophysics, Cambridge, Maryland 02138 and Pupillo, Guido and Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, 6020 Innsbruck and Porto, J. V.},
abstractNote = {We calculate entropy-temperature curves for interacting bosons in unit filled optical lattices for both homogeneous and harmonically trapped situations, and use them to understand how adiabatic changes in the lattice depth affect the temperature of the system. In a translationally invariant lattice, the zero tunneling limit facilitates a rather detailed analytic description. Unlike the noninteracting bosonic system which is always cooled upon adiabatic loading for low enough initial temperature, the change in the excitation spectrum induced by interactions can lead to heating. Finite tunneling helps to reduce this heating. Finally, we study the spatially inhomogeneous system confined in a parabolic potential and show that the presence of the trap can significantly reduce the final available temperature, due to the nonvanishing superfluid component at the edge of the cloud which is present in trapped systems.},
doi = {10.1103/PHYSREVA.73.023608},
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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