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arXiv · 1210.6974

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

K. Torokhtii·N. Pompeo·C. Meneghini·C. Attanasio·C. Cirillo·E. A. Ilyina·S. Sarti·E. Silva
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Abstract

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.

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K. Torokhtii, N. Pompeo, C. Meneghini, C. Attanasio, C. Cirillo, E. A. Ilyina, S. Sarti, E. Silva. 2012-10-25. Microwave properties of Nb/PdNi/Nb trilayers. Observation of flux flow in excess of Bardeen-Stephen theory. https://doi.org/10.1007/s10948-012-1795-7

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