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Collective excitations of trapped Fermi or Bose gases

A. Csordas·Z. Adam
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Abstract

A new method is developed to calculate all excitations of trapped gases using hydrodynamics at zero temperature for any equation of state $μ=μ(n)$ and for any trapping potential. It is shown that a natural scalar product can be defined for the mode functions, by which the wave operator is hermitian and the mode functions are orthogonal. It is also shown that the Kohn-modes are exact for harmonic trapping in hydrodynamic theory. Excitations for fermions are calculated in the BCS-BEC transition region using the equation of state of the mean-field Leggett-model for isotrop harmonic trap potential.

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A. Csordas, Z. Adam. 2005-12-22. Collective excitations of trapped Fermi or Bose gases. https://doi.org/10.1103/physreva.74.035602

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