Self-Energy on the Low- to High-Energy Electronic Structure of Correlated Metal SrVO3

The correlated electronic structure of SrVO3 has been investigated by angle-resolved photoemission spectroscopy using in situ prepared thin films. Pronounced features of band renormalization have been observed: a sharp kink similar to 60 meV below the Fermi level (E-F) and a broad so-called "high-energy kink" similar to 0.3 eV below E-F as in the high-T-c cuprates, although SrVO3 does not show magnetic fluctuations. We have deduced the self-energy in a wide energy range by applying the Kramers-Kronig relation to the observed spectra. The obtained self-energy clearly shows a large energy scale of similar to 0.7 eV, which is attributed to electron-electron interaction and gives rise to the similar to 0.3 eV kink in the band dispersion as well as the incoherent peak similar to 1.5 eV below E-F. The present analysis enables us to obtain a consistent picture for both the incoherent spectra and the band renormalization.