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Quasi-particle excitations and dynamical structure function of trapped Bose-condensates in the WKB approximation

András Csordás·Robert Graham·Péter Szépfalusy
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Abstract

The Bogoliubov equations of the quasi-particle excitations in a weakly interacting trapped Bose-condensate are solved in the WKB approximation in an isotropic harmonic trap, determining the discrete quasi-particle energies and wave functions by torus (Bohr-Sommerfeld) quantization of the integrable classical quasi-particle dynamics. The results are used to calculate the position and strengths of the peaks in the dynamic structure function which can be observed by off-resonance inelastic light-scattering.

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András Csordás, Robert Graham, Péter Szépfalusy. 1997-11-14. Quasi-particle excitations and dynamical structure function of trapped Bose-condensates in the WKB approximation. https://doi.org/10.1103/physreva.57.4669

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