Publication Scientific Reports Nature - A. Portavoce et al (RDI) "Magnetic moment impact on spin‑dependent Seebeck coefficient of ferromagnetic thin films"
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 investigated. μI 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.
Figure 2. Microstructures of the 50 nm-thick Mn5Ge3 film and of the 150 nm-thick MnxCoyGe1−x−y films. (a) X-ray diffractograms measured on Mn5Ge3 and MnxCoyGe1− x−y films. (b) AFM measurements performed on the film MnCoGe.
