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Canonical Bose gas simulations with stochastic gauges

P. D. Drummond·P. Deuar·K. V. Kheruntsyan
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Abstract

A technique to simulate the grand canonical ensembles of interacting Bose gases is presented. Results are generated for many temperatures by averaging over energy-weighted stochastic paths, each corresponding to a solution of coupled Gross-Pitaevskii equations with phase-noise. The stochastic gauge method used relies on an off-diagonal coherent-state expansion, thus taking into account all quantum correlations. As an example, the second order spatial correlation function and momentum distribution for an interacting 1D Bose gas are calculated.

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P. D. Drummond, P. Deuar, K. V. Kheruntsyan. 2004-02-26. Canonical Bose gas simulations with stochastic gauges. https://doi.org/10.1103/physrevlett.92.040405

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