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Selective d-state Conduction Blocking in Nickel Nanocontacts

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

The lowest conductance step for a Ni nanocontact is anomalously small in comparison with the large expected number of conducting channels. We present electronic structure calculations for an extremely idealized Ni nanobridge consisting of just a monatomic nanowire. Our calculations show that no less than eight single spin bands cross the Fermi level in a nonmagnetic Ni monatomic wire, dropping marginally to seven in the more stable, fully ferromagnetic state. However, when we build in the wire a magnetization reversal, or domain wall, by forcing the net magnetization to be zero, we suddenly find that d electrons selectively cease to propagate across the wall. s electron propagation remains, and can account for the small observed conductance steps.

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A. Smogunov, A. Dal Corso, E. Tosatti. 2001-11-20. Selective d-state Conduction Blocking in Nickel Nanocontacts. https://doi.org/10.1016/s0039-6028(02)01323-7

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