Quantum fluctuation induced time of flight correlations of an interacting trapped Bose gas

Abstract

We investigate numerically the momentum correlations in a two dimensional, harmonically trapped interacting Bose system at $T=0$ temperature, by using a particle number preserving Bogoliubov approximation. Interaction induced quantum fluctuations of the quasi-condensate lead to a large anti-correlation dip between particles of wave numbers $\mathbf{k}$ and $-\mathbf{k}$ for $|\mathbf{k}|\sim 1/R_c$, with $R_c$ typical size of the condensate. The anti-correlation dip found is a clear fingerprint of coherent quantum fluctuations of the condensate. In contrast, for larger wave numbers, $|\mathbf{k}|>>1/R_c$, a weak positive correlation is found between particles of wave numbers $\mathbf{k}$ and $-\mathbf{k}$, in accordance with the Bogoliubov result for homogeneous interacting systems.

13 pages, 8 figures, accepted version, minor changes and extended discussion

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Cited by in corpus (6)

• Bose-Einstein condensate fluctuations versus an interparticle interaction
• Full Counting Statistics of the momentum occupation numbers of the Tonks-Girardeau gas
• Entropy of a Turbulent Bose-Einstein Condensate
• Position- and momentum-space two-body correlations in a weakly interacting trapped condensate
• Statistical properties of the momentum occupation numbers of the Tonks-Girardeau gas in a harmonic trap
• $n$-body Correlation of Tonks-Girardeau Gas