Long-range spin imbalance in mesoscopic superconductors under a Zeeman splitting

I. V. Bobkova; A. M. Bobkov

doi:10.1134/s0021364015020022

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arXiv · 1412.0292

Long-range spin imbalance in mesoscopic superconductors under a Zeeman splitting

I. V. Bobkova·A. M. Bobkov

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Abstract

We develop a theory of spin relaxation in Zeeman-splitted superconducting films at low temperatures. A new mechanism of spin relaxation, specific only for Zeeman-splitted superconductors is proposed. It can explain the extremely high spin relaxation lengths, experimentally observed in Zeeman-splitted superconductors, and their strong growth with the magnetic field. In the framework of this mechanism the observed spin signal is formed by the spin-independent nonequilibrium quasiparticle distribution weighted by the spin-split DOS. We demonstrate that the relaxation length of such a spin signal is determined by the energy relaxation length at energies of the order of the superconducting gap.

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I. V. Bobkova, A. M. Bobkov. 2014-11-30. Long-range spin imbalance in mesoscopic superconductors under a Zeeman splitting. https://doi.org/10.1134/s0021364015020022

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