Spin-polarized electronic structures and transport properties of Fe-Co alloys

TL;DR

This paper calculates and compares the electrical resistivities and spin-polarization of Fe-Co alloys, revealing the dominant role of s-electrons in conductivity and discrepancies in spin-polarization estimates.

Contribution

It provides a quantitative analysis of electrical resistivities and spin-polarization in Fe-Co alloys using the Kubo-Greenwood formula, highlighting the electron contributions to transport properties.

Findings

Electrical resistivities agree with experimental data at low temperature.

Spin-polarization from conductivity and density of states have opposite signs.

Conductivity mainly governed by s-electrons, with minority spins less conductive.

Abstract

The electrical resistivities of Fe-Co alloys owing to random alloy disorder are calculated using the Kubo-Greenwood formula. The obtained electrical esistivities agree well with experimental data quantitatively at low temperature. The spin-polarization of Fe50Co50 estimated from the conductivity (86%) has opposite sign to that from the densities of the states at the Fermi level (-73%). It is found that the conductivity is governed mainly by s-electrons, and the s-electrons in the minority spin states are less conductive due to strong scattering by the large densities of the states of d-electrons than the majority spin electrons.