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On the stability of standing matter waves in a trap

A. E. Muryshev·H. B. van Linden van den Heuvell·G. V. Shlyapnikov
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Abstract

We discuss excited Bose-condensed states and find the criterion of dynamical stability of a kink-wise state, i.e., a standing matter wave with one nodal plane perpendicular to the axis of a cylindrical trap. The dynamical stability requires a strong radial confinement corresponding to the radial frequency larger than the mean-field interparticle interaction. We address the question of thermodynamic instability related to the presence of excitations with negative energy.

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A. E. Muryshev, H. B. van Linden van den Heuvell, G. V. Shlyapnikov. 1999-09-28. On the stability of standing matter waves in a trap. https://doi.org/10.1103/physreva.60.r2665

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