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Controlling spin supercurrents via nonequilibrium spin injection.

ABSTRACT: We propose a mechanism whereby spin supercurrents can be manipulated in superconductor/ferromagnet proximity systems via nonequilibrium spin injection. We find that if a spin supercurrent exists in equilibrium, a nonequilibrium spin accumulation will exert a torque on the spins transported by this current. This interaction causes a new spin supercurrent contribution to manifest out of equilibrium, which is proportional to and polarized perpendicularly to both the injected spins and the equilibrium spin current. This is interesting for several reasons: as a fundamental physical effect; due to possible applications as a way to control spin supercurrents; and timeliness in light of recent experiments on spin injection in proximitized superconductors.

SUBMITTER: Ouassou JA

PROVIDER: S-EPMC6744513 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Controlling spin supercurrents via nonequilibrium spin injection.

Ouassou Jabir Ali JA Robinson Jason W A JWA Linder Jacob J

Scientific reports 20190913 1

We propose a mechanism whereby spin supercurrents can be manipulated in superconductor/ferromagnet proximity systems via nonequilibrium spin injection. We find that if a spin supercurrent exists in equilibrium, a nonequilibrium spin accumulation will exert a torque on the spins transported by this current. This interaction causes a new spin supercurrent contribution to manifest out of equilibrium, which is proportional to and polarized perpendicularly to both the injected spins and the equilibri ...[more]

PMID: 31519921

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