The colossal magnetoresistance (LaxSn1-x)yMnO3-δ films studied by X-ray photoemission spectroscopy

(LaxSn1-x)(y)MnO3-delta (LSnMO) epitaxial films have been successfully grown on single-crystal (1 0 0) LaAlO3 substrates by pulsed-laser deposition (PLD). Measurements of magnetic and transport properties show that this material has colossal magnetoresistance (CMR) effect near the insulator-metal (IM) transition and paramagnetic-ferromagnetic (PF) phase transition. The core levels and the valence band of the film have been studied by X-ray photoemission spectroscopy (XPS). Through the study of angle-resolved X-ray photoemission spectroscopy (ARXPS), we find that the terminal layer of LSnMO film is the MnO atomic plane and there is a slight tin separating out in the film surface. On the basis of the above results and the crystalline structure of perovskite oxides, the growth mechanism of the LSnMO heteroepitaxy on (100) LaAlO3 substrate has been discussed. (C) 2000 Elsevier Science B.V. All rights reserved.