407 research outputs found
Dissipative dynamics of vortex arrays in anisotropic traps
We discuss the dissipative dynamics of vortex arrays in trapped
Bose-condensed gases and analyze the lifetime of the vortices as a function of
trap anisotropy and the temperature. In particular, we distinguish the two
regimes of the dissipative dynamics, depending on the relative strength of the
mutual friction between the vortices and the thermal component, and the
friction of the thermal particles on the trap anisotropy. We study the effects
of heating of the thermal cloud by the escaping vortices on the dynamics of the
system.Comment: RevTeX, 8 pages, 3 eps figure
Defect-Suppressed Atomic Crystals in an Optical Lattice
We present a coherent filtering scheme which dramatically reduces the site
occupation number defects for atoms in an optical lattice, by transferring a
chosen number of atoms to a different internal state via adiabatic passage.
With the addition of superlattices it is possible to engineer states with a
specific number of atoms per site (atomic crystals), which are required for
quantum computation and the realisation of models from condensed matter
physics, including doping and spatial patterns. The same techniques can be used
to measure two-body spatial correlation functions. We illustrate these ideas
with a scheme to study the creation of a BCS state with a chosen filling factor
from a degenerate Fermi gas in an optical lattice.Comment: 4 Pages, 5 Figures, REVTex
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