Critical Josephson current in BCS-BEC-crossover superfluids
Autori: Zaccanti M., Zwerger W.
Affiliazione autori: CNR, INO, I-50019 Sesto Fiorentino, Italy; Univ Firenze, LENS, I-50019 Sesto Fiorentino, Italy; Univ Firenze, Dipartimento Fis & Astron, I-50019 Sesto Fiorentino, Italy; Tech Univ Munich, Phys Dept, D-85748 Garching, Germany
Abstract: We develop a microscopic model to describe the Josephson tunneling between two superfluid reservoirs of ultracold fermionic atoms which accounts for the dependence of the critical current on both the barrier height and the interaction strength along the crossover from the BCS to the BEC regime. Building on a previous study [F. Meier and W. Zwerger, Phys. Rev. A 64, 033610 (2001)] of weakly interacting bosons, we derive analytic results for the Josephson critical current at zero temperature for homogeneous and trapped systems at arbitrary coupling. The critical current exhibits a maximum near the unitarity limit which arises from the competition between the increasing condensate fraction and a decrease in the chemical potential along the evolution from the BCS to the BEC limit. Our results agree quantitatively with numerical simulations and recent experimental data
Giornale/Rivista: PHYSICAL REVIEW A
Volume: 100 (6) Da Pagina: 063601-1 A: 063601-8
Parole chiavi: DOUBLE-WELL; SYMMETRY; FLOWDOI: 10.1103/PhysRevA.100.063601Citazioni: 13dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2022-05-22Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui