Density ripples in expanding low-dimensional gases as a probe of correlations

Details Density ripples in expanding low-dimensional gases as a probe of correlations Density ripples in expanding low-dimensional gases as a probe of correlations

2009-04-10

arxiv.org/abs/0904.1723v3

Phys. Rev. A 80, 033604 (2009)

Physics

Condensed Matter

Quantum Gases

Final published version

Scientific paper

10.1103/PhysRevA.80.033604

We investigate theoretically the evolution of the two-point density correlation function of a low-dimensional ultracold Bose gas after release from a tight transverse confinement. In the course of expansion thermal and quantum fluctuations present in the trapped systems transform into density fluctuations. For the case of free ballistic expansion relevant to current experiments, we present simple analytical relations between the spectrum of ``density ripples'' and the correlation functions of the original confined systems. We analyze several physical regimes, including weakly and strongly interacting one-dimensional (1D) Bose gases and two-dimensional (2D) Bose gases below the Berezinskii-Kosterlitz-Thouless (BKT) transition. For weakly interacting 1D Bose gases, we obtain an explicit analytical expression for the spectrum of density ripples which can be used for thermometry. For 2D Bose gases below the BKT transition, we show that for sufficiently long expansion times the spectrum of the density ripples has a self-similar shape controlled only by the exponent of the first-order correlation function. This exponent can be extracted by analyzing the evolution of the spectrum of density ripples as a function of the expansion time.

Affiliated with

Also associated with

No associations

Rating

Density ripples in expanding low-dimensional gases as a probe of correlations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Density ripples in expanding low-dimensional gases as a probe of correlations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Density ripples in expanding low-dimensional gases as a probe of correlations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-674223