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Charge and spin transport in mesoscopic superconductors.

ABSTRACT:

Background

Non-equilibrium charge transport in superconductors has been investigated intensely in the 1970s and 1980s, mostly in the vicinity of the critical temperature. Much less attention has been paid to low temperatures and the role of the quasiparticle spin.

Results

We report here on nonlocal transport in superconductor hybrid structures at very low temperatures. By comparing the nonlocal conductance obtained by using ferromagnetic and normal-metal detectors, we discriminate charge and spin degrees of freedom. We observe spin injection and long-range transport of pure, chargeless spin currents in the regime of large Zeeman splitting. We elucidate charge and spin transport by comparison to theoretical models.

Conclusion

The observed long-range chargeless spin transport opens a new path to manipulate and utilize the quasiparticle spin in superconductor nanostructures.

SUBMITTER: Wolf MJ

PROVIDER: S-EPMC3944028 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Charge and spin transport in mesoscopic superconductors.

Wolf M J MJ Hübler F F Kolenda S S Beckmann D D

Beilstein journal of nanotechnology 20140217

<h4>Background</h4>Non-equilibrium charge transport in superconductors has been investigated intensely in the 1970s and 1980s, mostly in the vicinity of the critical temperature. Much less attention has been paid to low temperatures and the role of the quasiparticle spin.<h4>Results</h4>We report here on nonlocal transport in superconductor hybrid structures at very low temperatures. By comparing the nonlocal conductance obtained by using ferromagnetic and normal-metal detectors, we discriminate ...[more]

PMID: 24605283

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