Photoemission and x-ray absorption spectroscopy study of electron-doped colossal magnetoresistance manganite: La0.7Ce0.3MnO3 film

摘要

The electronic structure of La0.7Ce0.3MnO3 (LCeMO) thin film has beeninvestigated using photoemission spectroscopy (PES) and x-ray absorptionspectroscopy (XAS). The Ce 3d core-level PES and XAS spectra of LCeMO are verysimilar to those of CeO2, indicating that Ce ions are far from being trivalent.A very weak 4f resonance is observed around the Ce 4d $\to$ 4f absorption edge,suggesting that the localized Ce 4f states are almost empty in the groundstate. The Mn 2p XAS spectrum reveals the existence of the Mn(2+) multipletfeature, confirming the Mn(2+)-Mn(3+) mixed-valent states of Mn ions in LCeMO.The measured Mn 3d PES/XAS spectra for LCeMO agrees reasonably well with thecalculated Mn 3d PDOS using the LSDA+U method. The LSDA+U calculation predictsa half-metallic ground state for LCeMO.