Coupled Dipole Oscillations of a Mass-Imbalanced Bose and Fermi Superfluid Mixture

Abstract

Recent experimental realizations of superfluid mixtures of Bose and Fermi quantum gases provide a unique platform for exploring diverse superfluid phenomena. We study dipole oscillations of a double superfluid in a cigar-shaped optical dipole trap, consisting of ${}^{41}$K and ${}^6$Li atoms with a large mass imbalance, where the oscillations of the bosonic and fermionic components are coupled via the Bose-Fermi interaction. In our high-precision measurements, the frequencies of both components are observed to be shifted from the single-species ones, and exhibit unusual features. The frequency shifts of the ${}^{41}$K component are upward (downward) in the radial (axial) direction, whereas the ${}^6$Li component has down-shifted frequencies in both directions. Most strikingly, as the interaction strength is varied, the frequency shifts display a resonant-like behavior in both directions, for both species, and around a similar location at the BCS side of fermionic superfluid. These rich phenomena challenge theoretical understanding of superfluids.

References in corpus (11)

• Many-Body Physics with Ultracold Gases
• Collective excitations of a degenerate gas at the BEC-BCS crossover
• The Equation of State of a Low-Temperature Fermi Gas with Tunable Interactions
• The `Higgs' Amplitude Mode at the Two-Dimensional Superfluid-Mott Insulator Transition
• Precision Measurements of Collective Oscillations in the BEC-BCS Crossover
• Two-Element Mixture of Bose and Fermi Superfluids
• The critical velocity in the BEC-BCS crossover
• Polaronic atom-trimer continuity in three-component Fermi gases
• Chandrasekhar-Clogston limit and critical polarization in a Fermi-Bose superfluid mixture
• Production of large ${}^{41}$K Bose-Einstein condensates using D1 gray molasses
• Narrow-linewidth cooling of ${}^6$Li atoms using the 2S-3P transition

Cited by in corpus (4)

• Breathing Mode of a BEC Repulsively Interacting with a Fermionic Reservoir
• Collective dynamics of Fermi-Bose mixtures with an oscillating scattering length
• BEC immersed in a Fermi sea: Theory of static and dynamic behavior across phase separation
• Nonlinear dynamics of coupled superfluids