Optimizing the proximity effect along the BCS side of the BCS-BEC crossover
Anno: 2018
Autori: Piselli V., Simonucci S., Strinati Calvanese G.
Affiliazione autori: Univ Carnerino, Phys Div, Sch Sci & Technol, I-62032 Carnerino, MC, Italy; INFN, Sez Perugia, I-06123 Perugia, PG, Italy; CNR, INO, Sede Firenze, I-50125 Florence, FI, Italy.
Abstract: The proximity effect, which arises at the interface between two fermionic superfluids with different critical temperatures, is examined with a nonlocal (integral) equation whose kernel contains information about the size of Cooper pairs that leak across the interface. This integral approach avoids reference to the boundary conditions at the interface that would be required with a differential approach. The temperature dependence of the pair penetration depth on the normal side of the interface is determined over a wide temperature range also varying the interparticle coupling along the BCS side of the BCS-BEC crossover independently on both sides of the interface. In this way, the size of Cooper pairs evolves from being much larger than (BCS limit) the interparticle distance to being comparable with (unitarity limit, halfway between the BCS and BEC limits) the interparticle distance. Conditions are then found for which the proximity effect is optimized in terms of the extension of the pair penetration depth.
Giornale/Rivista: PHYSICAL REVIEW B
Volume: 98 (14) Da Pagina: 144508-1 A: 144508-12
Parole chiavi: EquationDOI: 10.1103/PhysRevB.98.144508Citazioni: 5dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2024-10-27Riferimenti 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