Supercurrent decay in ballistic magnetic Josephson junctions
- URL: http://arxiv.org/abs/2101.10601v3
- Date: Sat, 25 Dec 2021 07:27:35 GMT
- Title: Supercurrent decay in ballistic magnetic Josephson junctions
- Authors: Herv\'e Ness, Ivan A. Sadovskyy, Andrey E. Antipov, Mark van
Schilfgaarde, Roman M. Lutchyn
- Abstract summary: We show how the supercurrent decays exponentially with thickness and identify two mechanisms responsible for the effect.
Our results for Nb/Ni/Nb junctions are in good agreement with recent experimental studies.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: 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 Bogoliubov-de
Gennes model and opens a path for material composition optimization in magnetic
Josephson junctions and superconducting magnetic spin valves.
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