Fermi Gases in Slowly Rotating Traps: Superfluid vs Collisional Hydrodynamics

TL;DR

This paper compares the dynamic responses of superfluid and normal Fermi gases in slowly rotating traps, highlighting differences in collective oscillations, vorticity effects, and hydrodynamic behavior.

Contribution

It provides a detailed hydrodynamic analysis of Fermi gases in rotating traps, emphasizing the distinct behaviors of superfluid and normal phases under dynamic conditions.

Findings

Normal gas exhibits vorticity-induced precession and beating.

Superfluid lacks vorticity effects, showing different oscillation patterns.

Hydrodynamic theory explains collective modes in rotating Fermi gases.

Abstract

The dynamic behavior of a Fermi gas confined in a deformed trap rotating at low angular velocity is investigated in the framework of hydrodynamic theory. The differences exhibited by a normal gas in the collisional regime and a superfluid are discussed. Special emphasis is given to the collective oscillations excited when the deformation of the rotating trap is suddenly removed or when the rotation is suddenly stopped. The presence of vorticity in the normal phase is shown to give rise to precession and beating phenomena which are absent in the superfluid phase.