Collective oscillations of a trapped Fermi gas near a Feshbach resonance

TL;DR

This paper calculates the collective oscillation frequencies of a trapped Fermi gas near a Feshbach resonance, revealing a non-monotonous dependence on interaction strength across different regimes.

Contribution

It provides a theoretical analysis of collective modes in a Fermi gas near a Feshbach resonance using hydrodynamic theory, covering multiple interaction regimes.

Findings

Radial mode frequency varies non-monotonously with scattering length.

Interaction effects significantly influence collective oscillation frequencies.

Theoretical predictions span molecular BEC to unitarity limit regimes.

Abstract

The frequencies of the collective oscillations of a harmonically trapped Fermi gas interacting with large scattering lengths are calculated at zero temperature using hydrodynamic theory. Different regimes are considered, including the molecular Bose-Einstein condensate and the unitarity limit for collisions. We show that the frequency of the radial compressional mode in an elongated trap exhibits a pronounced non monotonous dependence on the scattering length, reflecting the role of the interactions in the equation of state.