One-dimensional density waves of ultracold bosons in an optical lattice

Journal Article · Sun May 15 00:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.71.053606· OSTI ID:20717791

Kollath, C; Schollwoeck, U; Delft, J von; Zwerger, W ^[1]

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1. Institut fuer Theoretische Physik C, RWTH-Aachen, D-52056 Aachen (Germany) and Sektion Physik, Ludwig-Maximilians-Universitaet, Theresienstrasse 37/III, D-80333 Munich (Germany)

We investigate the propagation of density-wave packets in a Bose-Hubbard model using the adaptive time-dependent density-matrix renormalization group method. We discuss the decay of the amplitude with time and the dependence of the velocity on density, interaction strength, and the height of the perturbation in a numerically exact way, covering arbitrary interactions and amplitudes of the perturbation. In addition, we investigate the effect of self-steepening due to the amplitude dependence of the velocity and discuss the possibilities for an experimental detection of the moving wave packet in time-of-flight pictures. By comparing the sound velocity to theoretical predictions, we determine the limits of a Gross-Pitaevskii- or Bogoliubov-type description and the regime where repulsive one-dimensional Bose gases exhibit fermionic behavior.

• OSTI ID: 20717791
• Journal Information: Physical Review. A, Vol. 71, Issue 5; Other Information: DOI: 10.1103/PhysRevA.71.053606; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
BOSE-EINSTEIN CONDENSATION
BOSE-EINSTEIN GAS
BOSONS
DENSITY
DENSITY MATRIX
DETECTION
DISTURBANCES
FERMIONS
HUBBARD MODEL
ONE-DIMENSIONAL CALCULATIONS
RENORMALIZATION
SOUND WAVES
TIME DEPENDENCE
TIME-OF-FLIGHT METHOD
VELOCITY
WAVE PACKETS
WAVE PROPAGATION