magnetic-materials-2018-posters-abstracts

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S e p t e m b e r 2 4 - 2 6 , 2 0 1 8 | B u d a p e s t , H u n g a r y

OF EXCELLENCE

IN INTERNATIONAL

MEETINGS

YEARS

Magnetic Materials 2018

Materials Science and Nanotechnology

Volume 2

MAGNETISM AND

MAGNETIC MATERIALS

International Conference on

Mater Sci Nanotechnol 2018, Volume 2

STATIC AND DYNAMIC PROPERTIES OF JOSEPHSON JUNCTIONS

WITH COMPOSITE INSULATOR-SUPERCONDUCTOR-FERROMAGNETIC

INTERLAYER

Sergey Bakurskiy

Lomonosov Moscow State University, Russia

owadays the Josephson junctions with magnetic weak links attract special attention due to their possible applications

several future devices, such as superconducting MRAM, logic, quantum bits and neural networks. The interaction between

superconducting and ferromagnetic orders in the proximized area of ferromagnetic SFS junctions provides phenomenon

of 0- π oscillation of pairing amplitude in the structure. The effect permits to organize superconducting memory devices in

new principals. The S-IsF-S junction with composite interlayer consists of tunnel barrier I, thin superconducting film s and

ferromagnetic layer F combines high performance of the tunnel SIS junctions and special properties of magnetic SFS devices.

We developed a microscopic theory of the electron transport in these devices in the frame of the Usadel equations. We have

found that 0- π transition in SisFS junction can be hidden from the direct measurement its current-phase relation (CPR), due to

formation of multiple branches in the CPR shape. We demonstrate that the effect is the direct consequence of the significant

second harmonic in CPR of the ferromagnetic sFS part of the SisFS device. This fact significantly modifies modes of operation

of the structure. Furthermore, we predict the appearance of the superconducting phase domains in the thin superconductive

layer s near the domain walls in ferromagnetic material. The properties of the superconducting phase domains have hysteretic

nature and depend on the direction of injected current inside the structure.