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arXiv · 1709.04760

Proximity Effect in Superconducting-Ferromagnetic Granular Structures

Hadar Greener·Victor Shelukhin·Michael Karpovski·Moshe Goldstein·Alexander Palevski
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Abstract

We examined the proximity effect in granular films made of Pb, a superconductor, and Ni, a ferromagnet, with various compositions. Slow decay of the critical temperature as a function of the relative volume concentration of Ni per sample was demonstrated by our measurements, followed by a saturation of T$_c$. Using an approximate theoretical description of our granular system in terms of a layered one, we show that our data can only be reasonably fitted by a multilayer model. This indicates the importance of the interplay between different ferromagnetic grains; when non-collinearly magnetized they should lead to triplet Cooper pairing.

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Hadar Greener, Victor Shelukhin, Michael Karpovski, Moshe Goldstein, Alexander Palevski. 2017-09-14. Proximity Effect in Superconducting-Ferromagnetic Granular Structures. https://doi.org/10.1103/physrevb.97.014520

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