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Stability and collective excitations of a two-component Bose-condensed gas: a moment approach

Th. Busch·J. I. Cirac·V. M. Perez-Garcia·P. Zoller
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Abstract

The dynamics of a two-component dilute Bose gas of atoms at zero temperature is described in the mean field approximation by a two-component Gross-Pitaevskii Equation. We solve this equation assuming a Gaussian shape for the wavefunction, where the free parameters of the trial wavefunction are determined using a moment method. We derive equilibrium states and the phase diagrams for the stability for positive and negative s-wave scattering lengths, and obtain the low energy excitation frequencies corresponding to the collective motion of the two Bose condensates.

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Th. Busch, J. I. Cirac, V. M. Perez-Garcia, P. Zoller. 1997-05-01. Stability and collective excitations of a two-component Bose-condensed gas: a moment approach. https://doi.org/10.1103/physreva.56.2978

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