Josephson current in ballistic heterostructures with spin-active interfaces

Kalenkov, Mikhail S.
Galaktionov, Artem V.
Zaikin, Andrei D.
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We develop a general microscopic theory of dc Josephson effect in hybrid SNS structures with ballistic electrodes and spin-active NS interfaces. We establish a direct relation between the spectrum of Andreev levels and the Josephson current which contains complete information about non-trivial interplay between Andreev reflection and spin-dependent interface scattering. The system exhibits a rich structure of properties sensitive to spin-dependent barrier transmissions, spin-mixing angles, relative magnetization orientation of interfaces and the kinematic phase of scattered electrons. We analyze the current-phase relations and identify the conditions for the presence of a pi-junction state in the systems under consideration. We also analyze resonant enhancement of the supercurrent in gate-voltage-driven nanojunctions. As compared to the non-magnetic case, this effect can be strongly modified by spin-dependent scattering at NS interfaces.
Comment: 11 pages, 9 figures; version published in Phys. Rev. B
Condensed Matter - Superconductivity