Abstract
We have calculated the electronic structures of Co2FeAl1−x Si x (101) surface using first-principles method based on the density functional theory. Because of the surface effect, the minority spin band gap at the Fermi level disappears at the surface of bulk Co2FeAl1−x Si x . However, beneath the surface, the minority spin gap opens at the Fermi level, which indicates that the electronic structures of Co2FeAl1−x Si x (101) become close to that of bulk phase. Accordingly, the Co2FeAl1−x Si x (101) surface is a composite tri-layer structure that corresponds to the weakening of half-metallic property in Co2FeAl1−x Si x films. Even though, the spin polarization of Co2FeAl1−x Si x (101) surface is still larger than that of Co2FeAl or Co2FeSi materials, making Co2FeAl1−x Si x a promising spintronics material.
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Xu, X., Zhang, D., Wu, Y. et al. Electronic structures of Heusler alloy Co2FeAl1−x Si x surface. Rare Metals 31, 107–111 (2012). https://doi.org/10.1007/s12598-012-0472-0
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DOI: https://doi.org/10.1007/s12598-012-0472-0