Spin thermoelectric properties in fluorinated asymmetric zigzag SiC nanoribbons with boron and nitrogen impurities

Abstract

We investigated the spin caloritronic properties of zigzag silicon carbide nanoribbons with asymmetric fluorine edges (2F-8ZSiCNR-1F) doped with boron (B) or nitrogen (N) using density functional theory. Doping 2F-8ZSiCNRs-F with group III/V elements changes band structure states near the Fermi surface and modifies the systems magnetic moment. The doped structures exhibit magnetic metallic, half-metallic, and spin-semiconducting properties, with the dopant type and position significantly influencing spin-dependent thermoelectric properties. Pure thermal spin current reach 50–90 nA, while B and N doping induce perfect spin-filtering with negative differential thermal resistance. At zero chemical potential, the spin Seebeck coefficient (S_S) ranges from 0.01 mV K⁻¹ to 1.5 mV K⁻¹. These results highlight the potential of impurity engineering to enhance thermoelectric performance in spin caloritronic applications.