Nonlinear dynamics in a trapped atomic Bose-Einstein condensate induced by an oscillating Gaussian potential

Journal Article · Sun May 15 00:00:00 EDT 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.83.053609· OSTI ID:21546822

Fujimoto, Kazuya; Tsubota, Makoto ^[1]

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1. Department of Physics, Osaka City University, Sumiyoshi-ku, Osaka 558-8585 (Japan)

We consider a trapped atomic Bose-Einstein condensate penetrated by a repulsive Gaussian potential and theoretically investigate the dynamics induced by oscillating the Gaussian potential. Our study is based on the numerical calculation of the two-dimensional Gross-Pitaevskii equation. Our calculation reveals the dependence of the characteristic behavior of the condensate on the amplitude and frequency of the oscillating potential. These dynamics are deeply related to the nucleation and dynamics of quantized vortices and solitons. When the potential oscillates with a large amplitude, it nucleates many vortex pairs that move away from the potential. When the amplitude of the oscillation is small, it nucleates solitons through an annihilation of vortex pairs. We discuss three issues concerning the nucleation of vortices. The first is the phase diagram for the nucleation of vortices and solitons near the oscillating potential. The second is the mechanism and critical velocity of the nucleation. The critical velocity of the nucleation is an important issue in quantum fluids, and we propose an expression for the velocity containing both the coherence length and the size of the potential. The third is the divergence of the nucleation time, which is the time it takes for the potential to nucleate vortices, near the critical parameters for vortex nucleation.

• OSTI ID: 21546822
• Journal Information: Physical Review. A, Vol. 83, Issue 5; Other Information: DOI: 10.1103/PhysRevA.83.053609; (c) 2011 American Institute of Physics; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
ANNIHILATION
BOSE-EINSTEIN CONDENSATION
COHERENCE LENGTH
CRITICAL VELOCITY
EQUATIONS
GAUSS POTENTIAL
NONLINEAR PROBLEMS
NUCLEATION
OSCILLATIONS
PHASE DIAGRAMS
QUANTUM FLUIDS
SOLITONS
TRAPPING
TWO-DIMENSIONAL CALCULATIONS
VORTICES
DIAGRAMS
DIMENSIONS
FLUIDS
INFORMATION
INTERACTIONS
LENGTH
NUCLEON-NUCLEON POTENTIAL
PARTICLE INTERACTIONS
POTENTIALS
QUASI PARTICLES
VELOCITY