175 research outputs found
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
Dissipative dynamics of vortex arrays in trapped Bose-condensed gases: neutron stars physics on K scale
We develop a theory of dissipative dynamics of large vortex arrays in trapped
Bose-condensed gases. We show that in a static trap the interaction of the
vortex array with thermal excitations leads to a non-exponential decay of the
vortex structure, and the characteristic lifetime depends on the initial
density of vortices. Drawing an analogy with physics of pulsar glitches, we
propose an experiment which employs the heating of the thermal cloud in the
course of the decay of the vortex array as a tool for a non-destructive study
of the vortex dynamics.Comment: 4 pages, revtex; revised versio
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