2 research outputs found
Dynamic correlation functions in one-dimensional quasi-condensates
We calculate the static and dynamic single-particle correlation functions in
one-dimensional (1D) trapped Bose gases and discuss experimental measurements
that can directly probe such correlation functions. Using a quantized
hydrodynamic theory for the low energy excitations, we calculate both the
static and dynamic single-particle correlation functions for a 1D Bose gas that
is a phase-fluctuating quasi-condensate. For the static (equal-time)
correlation function, our approximations and results are equivalent to those of
Petrov, Shlyapnikov and Walraven. The Fourier transform of the static
single-particle correlation function gives the momentum distribution, which can
be measured using Doppler-sensitive Bragg scattering experiments on a highly
elongated Bose gas. We show how a two-photon Raman out-coupling experiment can
measure the characteristic features of the dynamic or time-dependent
single-particle correlation function of a 1D Bose quasi-condensate.Comment: 19 pages, 4 figures; submitted to Phys. Rev.
Finite-temperature correlations in the one-dimensional trapped and untrapped Bose gases
We calculate the dynamic single-particle and many-particle correlation
functions at non-zero temperature in one-dimensional trapped repulsive Bose
gases. The decay for increasing distance between the points of these
correlation functions is governed by a scaling exponent that has a universal
expression in terms of observed quantities. This expression is valid in the
weak-interaction Gross-Pitaevskii as well as in the strong-interaction
Girardeau-Tonks limit, but the observed quantities involved depend on the
interaction strength. The confining trap introduces a weak center-of-mass
dependence in the scaling exponent. We also conjecture results for the
density-density correlation function.Comment: 18 pages, Latex, Revtex