Rh polarization in ultrathin Rh layers on Fe(001)

Abstract

We discuss the origin of the Rh polarization at the interface with a semi-infinite Fe(001) crystal obtained through spin-resolved valence-band and core-level spectroscopy. Due to the fact that it is not yet known how Rh grows on Fe(001), we discuss different epitaxial arrangements of Rh atoms on Fe(001), i.e., not only the usual fcc and bcc configurations but also face-centered tetragonal (fct) and body-centered tetragonal (bct) configurations which conserve the atomic volume. The fcc and bcc configurations do not agree with the experimental results because the polarization of the Rh is long ranged for fcc and too small for bcc. fct and bct configurations appear to be more favorable. Moreover, in all cases investigated an oscillatory polarization of the Rh atoms has been obtained.