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Publication Citation: Optimization of Spin-triplet Supercurrent in Ferromagnetic Josephson Junctions

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Author(s): Benjamin James McMorran; Theresa Patricia Ginley; Julie A. Borchers; Brian J Kirby; Brian B. Maranville; John Unguris;
Title: Optimization of Spin-triplet Supercurrent in Ferromagnetic Josephson Junctions
Published: March 20, 2012
Abstract: In the past year, several groups have observed evidence for long-range spin-triplet, supercurrent in Josephson junctions containing ferromagnetic (F) materials. In our work, the spin-triplet pair correlations are created by non-collinear magnetizations between a central Co/Ru/Co "synthetic antiferromagnet" (SAF) and two outer think F layers. Here we present data showing that the spin-triplet supercurrent is enhanced up to 20 times after our samples are subject to a large in-plane magnetizing field. This surprising result can be explained if the Co/Ru/Co SAF undergones a "spin-flop" transition, whereby the two Co layer magnetizations end up perpendicular to the magnetizations of the two think F layers. Direct experimental evidence for the spin-flop transition comes from scanning electron microscopy with polarization analysis and from spin-polorized neutron reflectometry.
Citation: Physical Review Letters
Volume: 108
Issue: 12
Pages: pp. 127002-1 - 127002-5
Keywords: Josephson Junction; Supercurrent Effect; Spin-flop transition; Polarized neutron reflectivity; SEMPA
Research Areas: Condensed Matter Physics
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