The electronic structure of rare-earth iron silicide R2Fe3Si5 superconductors

TL;DR

This study uses first-principles calculations to analyze the electronic structures of R2Fe3Si5 superconductors, revealing that their properties are mainly influenced by Fe 3d states and local magnetic moments, rather than electronic structure at the Fermi level.

Contribution

The paper provides a detailed first-principles analysis of R2Fe3Si5 compounds, highlighting the dominance of Fe 3d states and the role of rare-earth magnetic moments in their superconducting behavior.

Findings

Most compounds have similar density of states at EF.

Electronic structure is dominated by Fe 3d states.

Superconducting differences relate to magnetic moments, not electronic structure.

Abstract

The electronic structures of R2Fe3Si5 (where R = Lu, Tm, Er, Tb, Yb) intermetallics have been calculated from first principles in local-spin density (LSDA) and LSDA + U approaches. The majority of rare-earth iron silicides, except for the heavy-fermion Yb-based compound, exhibit almost equal values of density of states at the Fermi level (EF) as well as very similar Fermi surface topology. The electronic structure around EF in the 235-type Fe-based compounds is completely dominated by the Fe 3d states. Thus the different superconducting properties of some members of the R2Fe3Si5 family are rather related to a presence of local magnetic moments of R-atoms than to electronic-structure features at EF.