In situ photoemission study on SrRuO3/SrTiO3 films grown by pulsed laser deposition -: art. no. 121406

Theelectronic structure Of STRuO3 film grown on SrTiO3 substrate is investigated in situ by ultraviolet and x-ray photoemission spectroscopy (XPS). The valence band spectrum shows the Ru 4d weight is transferred from the coherent part to the incoherent part due to the electron correlation effect among 4d electrons, but the amount of the spectral weight transfer is much less than the previous photoemission study on polycrystal samples with scraped surfaces and is consistent with the effective mass deduced from the specific heat measurements. Through 0 1s and Sr 3p core-level XPS measurements, it is found that while the in situ grown film Surface shows single-phase spectra, the scraped polycrystal samples exhibit some nonstoichiometric phases. Our study suggests that photoemission on in situ grown films can give information on the intrinsic electronic structures of transition metal oxides.