Signature of chemical potential shift in La_0.2Sr_0.8MnO₃

Abstract

We have investigated the temperature evolution of the electronic structure of La_0.2Sr_0.8MnO₃ using photoemission spectroscopy. Various core level spectra exhibit multiple peaks and interesting temperature dependence. Sr core level spectra indicate presence of satellite features as also observed in La core levels. Mn 2p spectra indicate distinct signature of Mn³⁺ and Mn⁴⁺ valence even in the metallic phase. Shift of the core levels with the variation in temperature indicate finite change in chemical potential across the phase transition.