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

TL;DR

This study investigates the electronic structure of La0.7Ce0.3MnO3 thin films using PES and XAS, revealing mixed-valent Mn states and nearly empty Ce 4f states, with theoretical calculations suggesting a half-metallic ground state.

Contribution

It provides detailed spectroscopic analysis of electron-doped manganite films and compares experimental results with LSDA+U calculations, highlighting the electronic states and valence configurations.

Findings

Ce ions are far from trivalent, similar to CeO2.

Mn ions exhibit mixed Mn(2+) and Mn(3+) valence states.

Theoretical calculations predict a half-metallic ground state.

Abstract

The electronic structure of La0.7Ce0.3MnO3 (LCeMO) thin film has been investigated using photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). The Ce 3d core-level PES and XAS spectra of LCeMO are very similar 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 ground state. The Mn 2p XAS spectrum reveals the existence of the Mn(2+) multiplet feature, 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 the calculated Mn 3d PDOS using the LSDA+U method. The LSDA+U calculation predicts a half-metallic ground state for LCeMO.