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arXiv · 0803.3664

Numerical method for evolving the Projected Gross-Pitaevskii equation

P. B. Blakie
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Abstract

In this paper we describe a method for evolving the projected Gross-Pitaevskii equation (PGPE) for a Bose gas in a harmonic oscillator potential. The central difficulty in solving this equation is the requirement that the classical field is restricted to a small set of prescribed modes that constitute the low energy classical region of the system. We present a scheme, using a Hermite-polynomial based spectral representation, that precisely implements this mode restriction and allows an efficient and accurate solution of the PGPE. We show equilibrium and non-equilibrium results from the application of the PGPE to an anisotropic trapped three-dimensional Bose gas.

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P. B. Blakie. 2008-07-20. Numerical method for evolving the Projected Gross-Pitaevskii equation. https://doi.org/10.1103/physreve.78.026704

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