Supercurrent decay in ballistic magnetic Josephson junctions  

作　　者：HervéNess Ivan A.Sadovskyy Andrey E.Antipov Mark van Schilfgaarde Roman M.Lutchyn 

机构地区：[1]Department of Physics,King’s College London,Strand Campus,London,WC2R 2LS,UK [2]Microsoft Quantum,Microsoft Station Q,University of California,Santa Barbara,CA,93106,USA [3]National Renewable Energy Laboratory,Golden,CO,80401,USA

出　　处：《npj Computational Materials》2022年第1期186-196,共11页计算材料学（英文）

基　　金：In the late stages of this work M.v.S.was supported by the U.S.Department of Energy,Office of Science,Basic Energy Sciences under Award#FWP ERW7906.

摘　　要：We investigate transport properties of ballistic magnetic Josephson junctions and establish that suppression of supercurrent is an intrinsic property of the junctions,even in absence of disorder.By studying the role of ferromagnet thickness,magnetization,and crystal orientation we show how the supercurrent decays exponentially with thickness and identify two mechanisms responsible for the effect:(i)large exchange splitting may gap out minority or majority carriers leading to the suppression of Andreev reflection in the junction,(ii)loss of synchronization between different modes due to the significant dispersion of the quasiparticle velocity with the transverse momentum.Our results for Nb/Ni/Nb junctions are in good agreement with recent experimental studies.Our approach combines density functional theory and the Bogoliubov-de Gennes model and opens a path for material composition optimization in magnetic Josephson junctions and superconducting magnetic spin valves.

关 键 词：JOSEPHSON DECAY MAGNETIC 

分 类 号：O51[理学—低温物理]