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arXiv · 1004.0442

Short-Wave Excitations in Non-Local Gross-Pitaevskii Model

A. P. Ivashin·Yu. M. Poluektov
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Abstract

It is shown, that a non-local form of the Gross-Pitaevskii equation allows to describe not only the long-wave excitations, but also the short-wave ones in the systems with Bose-condensate. At given parameter values, the excitation spectrum mimics the Landau spectrum of quasi-particle excitations in superfluid Helium with roton minimum. The excitation wavelength, at which the roton minimum exists, is close to the inter-particle interaction range. It is shown, that the existence domain of the spectrum with a roton minimum is reduced, if one accounts for an inter-particle attraction.

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A. P. Ivashin, Yu. M. Poluektov. 2010-04-03. Short-Wave Excitations in Non-Local Gross-Pitaevskii Model. https://doi.org/10.2478/s11534-010-0124-7

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