0000000000215167

AUTHOR

Kostiantyn Torokhtii

showing 2 related works from this author

Microwave Properties of Nb/PdNi/Nb Trilayers

2012

We combine wideband (1-20 GHz) Corbino disk and dielectric resonator (8.2 GHz) techniques to study the microwave properties in Nb/PdNi/Nb trilayers, grown by UHV dc magnetron sputtering, composed by Nb layers of nominal thickness $d_S$=15 nm, and a ferromagnetic PdNi layer of thickness $d_F$= 1, 2, 8 and 9 nm. We focus on the vortex state. Magnetic fields up to $H_{c2}$ were applied. The microwave resistivity at fixed $H/H_{c2}$ increases with $d_F$, eventually exceeding the Bardeen Stephen flux flow value.

SuperconductivityMaterials scienceStrongly Correlated Electrons (cond-mat.str-el)Condensed matter physicsCondensed Matter - SuperconductivityFOS: Physical sciencesDielectric resonatorSputter depositionCondensed Matter PhysicsVortex stateElectronic Optical and Magnetic MaterialsMagnetic fieldSuperconductivity (cond-mat.supr-con)Condensed Matter - Strongly Correlated ElectronsFerromagnetismElectrical resistivity and conductivityMicrowaveJournal of Superconductivity and Novel Magnetism
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Vortex motion in Nb/PdNi/Nb trilayers: new aspects in the flux flow state

2011

We study the dynamics of vortex lines in Supercondutor/Ferromagnet/Superconductor (SFS) heterostructures at microwave frequencies. We have employed swept-frequency, Corbino-disk and resonant, dielectric-resonator techniques to obtain the field and temperature dependence of the vortex-state parameters. We concentrate here on the genuine flux-flow resistivity $\rho_{ff}$, that we access at subcritical currents using a sufficiently high driving frequency. We find that $\rho_{ff}$ does not follow the well-known Bardeen-Stephen model. Instead, it is well described by a full time-dependent Ginzburg-Landau expression at very thin F layer thickness, but changes to a previously unreported field-depe…

SuperconductivityMaterials scienceField (physics)Condensed matter physicsCondensed Matter - SuperconductivityEnergy Engineering and Power TechnologyFOS: Physical sciencesDielectric resonatorVorticityCondensed Matter PhysicsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectElectronic Optical and Magnetic MaterialsVortexSuperconductivity (cond-mat.supr-con)FerromagnetismElectrical resistivity and conductivityCondensed Matter::SuperconductivityElectrical and Electronic Engineeringsuperconductors; nb; mixed state; s/f hybrids; dielectric resonator; resistance; vortex dynamics; surface impedance; corbino disk; vortices; temperatureMicrowave
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