Аннотация:In recent years Josephson junctions with ferromagnetic F layers became one of the most desirable
and actively developed devices in superconductive electronics. The oscillating nature of
superconductive proximity effect in the magnetics leads to appearance of π state and provides
opportunities to develop a wide range of applications. Among them there are memory elements,
improved RSFQ circuits and metamaterial elements.
Unfortunately, characteristic voltage, ICRN, of conventional SFS junctions is much smaller than
that of tunnel SIS devices, which are widely used in superconductive electronics. This leads to
deficient value of characteristic frequency and to difficulties in integration with other circuits.
As possible way to solve this task we
considered Josephson SIsFS structures
with complex interlayer consisting of
tunnel barrier ‗I‘, ferromagnetic layer ‗F‘
and thin superconductor layer ‗s‘ and we
outlined operational modes of these
junction. Due to superconductive support
inside weak link this structure achieves
both high frequency and has magnetic
properties. Thus SIsFS can be used as
high-speed π junction or memory element
[1-2].
However pairing in the thin middle
superconductive film ‗s‘ suffers from
proximity effect with ferromagnetic layer
and stays in the critical regime. It means
that state of that layer significantly
depends from inhomogeneities in
ferromagnetic layer. We study impact on
current properties of different types of
inhomogeneities including domains walls and normal phase inclusions.
This work was supported in part by the Ministry of Education and Science of the Russian
Federation, President grant MK-1841.2014.2, President Scholarship and RFBR grants 14-02-90018,
14-02-31002_mol_a.
[1] T. I. Larkin, V. V. Bol'ginov, V. S. Stolyarov, V. V. Ryazanov, I. V. Vernik, S. K. Tolpygo, and
O. A. Mukhanov, Appl. Phys. Lett. 100, 222601 (2012).
[2] S. V. Bakurskiy, N. V. Klenov, I. I. Soloviev, M. Yu. Kupriyanov, A. A. Golubov, Physical
Review B, 88 (14), 144519 (2013).