The electronic structure of rare-earth iron silicide R2Fe3Si5 superconductors

摘要

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 ofdensity of states at the Fermi level (EF) as well as very similar Fermi surfacetopology. The electronic structure around EF in the 235-type Fe-based compoundsis completely dominated by the Fe 3d states. Thus the different superconductingproperties of some members of the R2Fe3Si5 family are rather related to apresence of local magnetic moments of R-atoms than to electronic-structurefeatures at EF.