Interface hybridization and spectral distribution in strongly correlated itinerant magnetic systems.

Abstract

We report the results of a theoretical study of the effect of the interface s-d hybridization on the photoemission spectral distribution in a one-monolayer Co on Cu(001) structure. The single-particle electronic structure and many-body interactions are treated on an equal footing in a numerical scheme that incorporates both band-structure and interaction effects. Using exact diagonalization method on small clusters with periodic boundary conditions, spin- and angle-resolved photoemission spectra are calculated. We study the effect of the interface hybridization on the spectral distribution by first calculating the spectra of an unsupported Co(001) monolayer in the absence of the substrate. Then we calculate the spectra with the substrate included. In the latter case, the s-d hybridization is first turned off to isolate the contribution from the crystal-field effect. Eventually, the one-monolayer Co on Cu(001) with full interface s-d hybridization, the realistic system, is studied. The calculated spectra are analyzed in a many-body picture and compared to available experimental data. Further experimental measurements are called for to test some theoretically predicted features.