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Collapse and revival of excitations in Bose-Einstein condensates

M. Mottonen·S. M. M. Virtanen·M. M. Salomaa
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Abstract

We study the energies and decay of elementary excitations in weakly interacting Bose-Einstein condensates within a finite-temperature gapless second-order theory. The energy shifts for the high-lying collective modes turn out to be systematically negative compared with the Hartree-Fock-Bogoliubov-Popov approximation and the decay of the low-lying modes is found to exhibit collapse and revival effects. In addition, perturbation theory is used to qualitatively explain the experimentally observed Beliaev decay process of the scissors mode.

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M. Mottonen, S. M. M. Virtanen, M. M. Salomaa. 2005-02-18. Collapse and revival of excitations in Bose-Einstein condensates. https://doi.org/10.1103/physreva.71.023604

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