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

Abstract

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.