Ballistic conductance of magnetic Co and Ni nanowires with ultrasoft pseudopotentials

The scattering-based approach for calculating the ballistic conductance of open quantum systems is generalized to deal with magnetic transition metals as described by ultrasoft pseudopotentials. As an application we present quantum-mechanical conductance calculations for monatomic Co and Ni nanowires with a magnetization reversal. We find that in both Co and Ni nanowires, at the Fermi energy, the conductance of $d$ electrons is blocked by a magnetization reversal, while the $s$ states (one per spin) are perfectly transmitted. $d$ electrons have a nonvanishing transmission in a small energy window below the Fermi level. Here, transmission is larger in Ni than in Co.