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A Closed Class of Hydrodynamical Solutions for the Collective Excitations of a Bose-Einstein Condensate

Pippa Storey·Maxim Olshanii
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Abstract

A trajectory approach is taken to the hydrodynamical treatment of collective excitations of a Bose-Einstein condensate in a harmonic trap. The excitations induced by linear deformations of the trap are shown to constitute a broad class of solutions that can be fully described by a simple nonlinear matrix equation. An exact closed-form expression is obtained for the solution describing the mode {n=0, m=2} in a cylindrically symmetric trap, and the calculated amplitude-dependent frequency shift shows good agreement with the experimental results of the JILA group.

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Pippa Storey, Maxim Olshanii. 2002-01-11. A Closed Class of Hydrodynamical Solutions for the Collective Excitations of a Bose-Einstein Condensate. https://doi.org/10.1103/physreva.62.033604

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