Wideband microwave measurements in Nb/Pd${}_{84}$Ni${}_{16}$/Nb structures and comparison with thin Nb films

Abstract

We present wideband microwave measurements (1-22 GHz) taken on Superconductor/Ferromagnet heterostructures with the Corbino disk technique. We apply the technique to Nb/PdNi/Nb trilayers in the vortex state and we compare the results to data taken with the same technique on a Nb thin film. We show that it is possible to directly extract the genuine flux-flow resistivity from our frequency-dependent measurements without overcoming the (depinning) critical current. The characteristic frequency for vortex relaxation can also be estimated, without resorting to a specific model. We find that the F layer determines a weakening of pinning and an enhancement of the flux-flow resistivity with respect to the Nb film.

15 pages, submitted to Supercond. Sci. Technol., special issue on Hybrid Magnetic/Superconducting Systems

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Cited by in corpus (1)

• Microwave properties of Nb/PdNi/Nb trilayers. Observation of flux flow in excess of Bardeen-Stephen theory