2005/05/31 by R. Mélin
Physics and Astronomy · #Coherence (philosophical gambling strategy) #Coherence length #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Current (fluid) #Ferromagnetism #Josephson effect #Materials science #Physics #Physics of Superconductivity and Magnetism #Pi Josephson junction #Quantum and electron transport phenomena #Quantum mechanics #Range (aeronautics) #Superconductivity #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.72.134508
published as Phys. Rev. B 72, 134508 (2005) · 8 pages, 3 figures, modifications in the presentation
arxiv created 2005/07/01 · openalex publication_date 2005/10/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the crossed Josephson effect in a geometry consisting of a double ferromagnetic bridge between two superconductors, with tunnel interfaces. The crossed Josephson current vanishes on average because the Andreev-reflected hole does not follow the same sequence of impurities as the incoming electron. We show that (i) the root mean square of the crossed Josephson current distribution is proportional to the square root of the junction area and (ii) the coherent coupling mediated by fluctuations is ``long range'' since it decays over the ferromagnet phase coherence length l_\ensuremathφ, larger than the exchange length. We predict a crossed Josephson current due to fluctuations if the length of the ferromagnets is smaller than l_\ensuremathφ and larger than the exchange length \ensuremathξh.