Controlling the proximity in a Co/Nb multilayer: the properties of electronic transport

We present both a theoretical and experimental investigation of the proximity effect in a stack-like superconductor/ferromagnet (S/F) superlattice, where ferromagnetic layers with different thicknesses and coercive fields are made of Co. Calculations based on Usadel equations allow us to find conditions at which switching from the parallel to the antiparallel alignment of neighboring F-layers leads to a significant change of the superconducting order parameter in thin s-films. Experimentally we study the transport properties of a lithographically patterned Nb/Co multilayer. We observe that the resistive transition of the multilayer contains multiple steps, which we attribute to the transition of individual s-layers with T c’s depending on the local magnetization orientation of neighbor F-layers. We argue that such superlattices can be used as tunable kinetic inductors, designed for artificial neural networks with a representation of information in the current domain.

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Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.118 ◽

2020 ◽

Vol 11 ◽

pp. 1336-1345 ◽

Cited By ~ 2

Author(s):

Sergey Bakurskiy ◽

Mikhail Kupriyanov ◽

Nikolay V Klenov ◽

Igor Soloviev ◽

Andrey Schegolev ◽

...

Keyword(s):

Electronic Transport ◽

Proximity Effect ◽

Superconducting Order Parameter ◽

Experimental Investigations ◽

Resistive Transition ◽

Local Magnetization ◽

Ferromagnetic Layers ◽

Magnetization Orientation ◽

Usadel Equations ◽

A Current

We present both theoretical and experimental investigations of the proximity effect in a stack-like superconductor/ferromagnetic (S/F) superlattice, where ferromagnetic layers with different thicknesses and coercive fields are made of Co. Calculations based on the Usadel equations allow us to find the conditions at which switching from the parallel to the antiparallel alignment of the neighboring F-layers leads to a significant change of the superconducting order parameter in superconductive thin films. We experimentally study the transport properties of a lithographically patterned Nb/Co multilayer. We observe that the resistive transition of the multilayer structure has multiple steps, which we attribute to the transition of individual superconductive layers with the critical temperature, T c, depending on the local magnetization orientation of the neighboring F-layers. We argue that such superlattices can be used as tunable kinetic inductors designed for artificial neural networks representing the information in a “current domain”.

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Experimental probe of the spatial dependence of the superconducting order parameter: Kinetic inductance studies of the proximity effect

Journal of Low Temperature Physics ◽

10.1007/bf00655269 ◽

1976 ◽

Vol 24 (3-4) ◽

pp. 443-448 ◽

Cited By ~ 2

Author(s):

J. D. Lejeune ◽

D. G. Naugle

Keyword(s):

Proximity Effect ◽

Spatial Dependence ◽

Order Parameter ◽

Superconducting Order Parameter ◽

Kinetic Inductance

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Superconducting Order Parameter Nucleation and Critical Currents in the Presence of Weak Stray Fields in Superconductor/Insulator/Ferromagnet Hybrids

Coatings ◽

10.3390/coatings11050507 ◽

2021 ◽

Vol 11 (5) ◽

pp. 507

Author(s):

Vasiliy N. Kushnir ◽

Serghej L. Prischepa ◽

Michela Trezza ◽

Carla Cirillo ◽

Carmine Attanasio

Keyword(s):

Phenomenological Theory ◽

Critical Currents ◽

Superconducting Phase ◽

Stray Field ◽

Superconducting Properties ◽

Ginzburg Landau ◽

Ferromagnetic Layers ◽

Linearized System ◽

Critical Current Density Jc ◽

Usadel Equations

The stray fields produced by ferromagnetic layers in Superconductor/Insulator/Ferromagnet (S/I/F) heterostructures may strongly influence their superconducting properties. Suitable magnetic configurations can be exploited to manipulate the main parameters of the hybrids. Here, the nucleation of the superconducting phase in an external magnetic field that periodically oscillates along the film width is studied on the base of the numerical solution of the linearized system of Usadel equations. In addition, the effect of the magnetic configuration of the F-layer on the temperature dependence of the critical current density, Jc(T), is investigated in the framework of the Ginzburg–Landau phenomenological theory on the base of the oscillating model of a stray field. By following this approach, the Jc(T) dependence of a Nb/SiO2/PdNi trilayer is reproduced for different magnetic configurations of the PdNi layer.

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