Collective excitations of a trapped Fermi gas at finite temperature

A. Korolyuk; J. J. Kinnunen; P. Törmä

doi:10.1103/physreva.89.013602

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arXiv · 1307.1294

Collective excitations of a trapped Fermi gas at finite temperature

A. Korolyuk·J. J. Kinnunen·P. Törmä

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Abstract

We study collective excitations of a trapped Fermi gas at finite temperature using the Bogoliubov-deGennes mean-field theory in conjunction with the generalized random phase approximation. The collective excitations are analyzed through the density response of a monopole excitation. We show the appearance of several modes at the normal fluid - superfluid phase transition temperature: Higgs mode-like pairing amplitude modulations, analogues of the second sound in the trapped gas, and an edge mode that is also the strongest mode in the response.

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A. Korolyuk, J. J. Kinnunen, P. Törmä. 2013-11-08. Collective excitations of a trapped Fermi gas at finite temperature. https://doi.org/10.1103/physreva.89.013602

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