Optimizing the proximity effect along the BCS-BEC crossover

Abstract

The proximity effect, which arises at the interface between two fermionic superfluids with different critical temperatures, is examined with a non-local (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 inter-particle coupling along the BCS-BEC crossover independently on both sides of the interface. Conditions are found for which the proximity effect is optimized in terms of the extension of the pair penetration depth.

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Cited by in corpus (5)

• Josephson effect at finite temperature along the BCS-BEC crossover
• Proximity effect and spatial Kibble-Zurek mechanism in atomic Fermi gases with inhomogeneous pairing interactions
• Self-consistent evaluation of proximity and inverse proximity effects with pair-breaking in diffusive SN junctions
• Inclusion of pairing fluctuations in a semiclassical approach: The case of study of the Josephson effect
• Structures and proximity effects of inhomogeneous population-imbalanced Fermi gases with pairing interactions