Short-wave excitations in non-local Gross-Pitaevskii model

  title={Short-wave excitations in non-local Gross-Pitaevskii model},
  author={A. Ivashin and Y. Polu{\'e}ktov},
  journal={Central European Journal of Physics},
We show that a non-local form of the Gross-Pitaevskii equation describes not only long-wave excitations, but also the short-wave ones in Bose-condensate systems. At certain 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. We determine how the roton gap and the effective roton mass depend on the… Expand

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