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Ballistic conductance of magnetic Co and Ni nanowires with ultrasoft pseudo-potentials

A. Smogunov·A. Dal Corso·E. Tosatti
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Abstract

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 pseudo-potentials. 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 non-vanishing transmission in a small energy window below the Fermi level. Here, transmission is larger in Ni than in Co.

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A. Smogunov, A. Dal Corso, E. Tosatti. 2004-05-19. Ballistic conductance of magnetic Co and Ni nanowires with ultrasoft pseudo-potentials. https://doi.org/10.1103/physrevb.70.045417

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