Density response of a trapped Fermi gas: a crossover from the pair vibration mode to the Goldstone mode

A. Korolyuk; J. J. Kinnunen; P. Törmä

doi:10.1103/physreva.84.033623

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arXiv · 1106.0430

Density response of a trapped Fermi gas: a crossover from the pair vibration mode to the Goldstone mode

A. Korolyuk·J. J. Kinnunen·P. Törmä

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Abstract

We consider the density response of a trapped two-component Fermi gas. Combining the Bogoliubov-deGennes method with the random phase approximation allows the study of both collective and single particle excitations. Calculating the density response across a wide range of interactions, we observe a crossover from a weakly interacting pair vibration mode to a strongly interacting Goldstone mode. The crossover is associated with a depressed collective mode frequency and an increased damping rate, in agreement with density response experiments performed in strongly interacting atomic gases.

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A. Korolyuk, J. J. Kinnunen, P. Törmä. 2011-10-27. Density response of a trapped Fermi gas: a crossover from the pair vibration mode to the Goldstone mode. https://doi.org/10.1103/physreva.84.033623

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