2018/02/08 by Peng Zou, Lianyi He, Xia-Ji Liu +1
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Feshbach resonance #Molecule #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Quantum, superfluid, helium dynamics #Superfluidity #cond-mat.quant-gas
paper · pdf · doi:10.1103/physreva.97.043616
published as Phys. Rev. A 97, 043616 (2018) · 13 pages, 9 figures
arxiv created 2018/02/08 · openalex publication_date 2018/04/17 · arxiv updated 2018/04/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the nature of superfluid pairing in a strongly interacting Fermi gas near orbital Feshbach resonances with spin-population imbalance in three dimensions, which can be well described by a two-band or two-channel model. We show that a Sarma superfluid with gapless single-particle excitations is favored in the closed channel at large imbalance. It is thermodynamically stable against the formation of an inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov superfluid and features a well-defined Goldstone-Anderson-Bogoliubov phonon mode and a massive Leggett mode as collective excitations at low momentum. At large momentum, the Leggett mode disappears and the phonon mode becomes damped at zero temperature, due to the coupling to the particle-hole excitations. We discuss possible experimental observation of a strongly interacting Sarma superfluid with ultracold alkaline-earth-metal Fermi gases.