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arXiv · 1111.5809

Long range spin supercurrents in ferromagnetic CrO$_2$ using a multilayer contact structure

M. S. Anwar·M. Veldhorst·A. Brinkman·J. Aarts
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Abstract

e report measurements of long ranged supercurrents through ferromagnetic and fully spin-polarized CrO$_2$ deposited on TiO$_2$ substrates. In earlier work, we found supercurrents in films grown on sapphire but not on TiO$_2$. Here we employed a special contact arrangement, consisting of a Ni/Cu sandwich between the film and the superconducting amorphous Mo$_{70}$Ge$_{30}$ electrodes. The distance between the contacts was almost a micrometer, and we find the critical current density to be significantly higher than found in the films deposited on sapphire. We argue this is due to spin mixing in the Ni/Cu/CrO$_2$ layer structure, which is helpful in the generation of the odd-frequency spin triplet correlations needed to carry the supercurrent.

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M. S. Anwar, M. Veldhorst, A. Brinkman, J. Aarts. 2011-11-24. Long range spin supercurrents in ferromagnetic CrO$_2$ using a multilayer contact structure. https://doi.org/10.1063/1.3681138

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