Changes in screening and electron density across the coupled metallic-magnetic phase transition of La 1− xCa xMnO 3

Abstract

We have observed the temperature dependence of the local electron screening across the nonmetal-metal transition of the transition metal oxide La 0.65Ca 0.35MnO 3 using resonant photoemission spectroscopy. In addition, a measurable change in the density of states near the Fermi level as a function of temperature was also observed. These changes in screening and electronic structure across the transition correlate well with both the bulk resistivity and magnetization. Energy shifts of the valence bands indicated that the Mn 3d-O 2p hybridization and charge distribution changed across the transition, consistent with theoretical models.