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arXiv · 1502.05991

Temporal and spatio-temporal correlation functions for trapped Bose gases

M. Kohnen·R. A. Nyman
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Abstract

Density correlations unambiguously reveal the quantum nature of matter. Here, we study correlations between measurements of density in cold-atom clouds at different times at one position, and also at two separated positions. We take into account the effects of finite-size and -duration measurements made by light beams passing through the atom cloud. We specialise to the case of Bose gases in harmonic traps above critical temperature, for weakly-perturbative measurements. For overlapping measurement regions, shot-noise correlations revive after a trap oscillation period. For non-overlapping regions, bosonic correlations dominate at long times, and propagate at finite speeds. Finally, we give a realistic measurement protocol for performing such experiments.

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M. Kohnen, R. A. Nyman. 2014-11-12. Temporal and spatio-temporal correlation functions for trapped Bose gases. https://doi.org/10.1103/physreva.91.033612

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