Spin supercurrent and phase-tunable triplet Cooper pairs via magnetic insulators
Journal article
Submitted version
Permanent lenke
http://hdl.handle.net/11250/2465150Utgivelsesdato
2015Metadata
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- Institutt for fysikk [2652]
- Publikasjoner fra CRIStin - NTNU [37215]
Originalversjon
10.1103/PhysRevB.92.035416Sammendrag
We demonstrate theoretically that a dissipationless spin current can flow a long distance through a diffusive normal metal by using superconductors interfaced with magnetic insulators. The magnitude of this spin supercurrent is controlled via the magnetization orientation of the magnetic insulators. The spin supercurrent obtained in this way is conserved in the normal metal just like the charge current and interestingly has a term that is independent of the superconducting phase difference. The quantum state of the system can be switched between 0 and π by reversing the insulators from a parallel to antiparallel configuration with an external field. We show that the spin current is carried through the normal metal by superconducting triplet (odd-frequency) correlations and that the superconducting phase difference can be used to enhance these, leaving clear spectroscopic fingerprints in the density of states.