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Magnetic moment impact on spin-dependent Seebeck coefficient of ferromagnetic thin films.

ABSTRACT: Magnetic materials may be engineered to produce thermoelectric materials using spin-related effects. However, clear understanding of localized magnetic moments (µ_I), free carriers, and Seebeck coefficient (S) interrelations is mandatory for efficient material design. In this work, we investigate µ_I influence on the spin-dependent S of model ferromagnetic thin films, allowing µ_I thermal fluctuations, ordering, and density variation influence to be independently investigated. µ_I influence on free carrier polarization is found to be of highest importance on S: efficient coupling of free carrier spin and localized magnetic moment promotes the increase of S, while spin-dependent relaxation time difference between the two spin-dependent conduction channels leads to S decrease. Our observations support new routes for thermoelectric material design based on spin-related effects in ferromagnetic materials.

SUBMITTER: Portavoce A

PROVIDER: S-EPMC9813267 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Magnetic moment impact on spin-dependent Seebeck coefficient of ferromagnetic thin films.

Portavoce Alain A Assaf Elie E Bertoglio Maxime M Narducci Dario D Bertaina Sylvain S

Scientific reports 20230104 1

Magnetic materials may be engineered to produce thermoelectric materials using spin-related effects. However, clear understanding of localized magnetic moments (µI), free carriers, and Seebeck coefficient (S) interrelations is mandatory for efficient material design. In this work, we investigate µI influence on the spin-dependent S of model ferromagnetic thin films, allowing µI thermal fluctuations, ordering, and density variation influence to be independently in ...[more]

PMID: 36599898

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