2007/04/18 by Jan Hammer, J. C. Hammer, Juan Carlos Cuevas +4 · 90 citations
Physics and Astronomy · #Condensed matter physics #Density of states #Josephson effect #Magnetic field #Materials science #Nanotechnology #Physics #Physics of Superconductivity and Magnetism #Proximity effect (electron beam lithography) #Quantum and electron transport phenomena #Quantum mechanics #Scattering #Spin (aerodynamics) #Spin-flip #Superconductivity #Superconductivity in MgB2 and Alloys #Supercurrent #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.76.064514
published in Physical Review B 76(6) (American Physical Society) · 12 pages, 13 figures
arxiv created 2007/04/18 · openalex publication_date 2007/08/14 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a theoretical study of the density of states and supercurrent in diffusive superconductor-normal metal-superconductor (SNS) junctions. In particular, we study the influence on these two equilibrium properties of both an arbitrary transparency of the SN interfaces and the presence of spin-flip scattering in the normal wire. We show that the minigap that is present in the spectrum of the diffusive wire is very sensitive to the interface transmission. More importantly, we show that at arbitrary transparency the minigap replaces the Thouless energy as the relevant energy scale for the proximity effect, determining, for instance, the temperature dependence of the critical current. We also study in detail how the critical current is suppressed by the effect of spin-flip scattering, which can be due either to magnetic impurities or, under certain circumstances, to an external magnetic field. Our analysis based on the quasiclassical theory of diffusive superconductors can be very valuable in establishing quantitative comparisons between experiment and theory.