Partial density of 3d electrons in CrSi probed by resonant photoemission

Abstract

Resonant photoemission has been performed on CrSi across the Cr 3p-3d transition by varying the photon excitation energies at the Indus synchrotron source. Resonant photoemission is an effective tool to determine the partial density of states. In the present work, Cr 3d states in CrSi has been probed to understand the change in the nature of the 3d electrons across the magnetic phase transition from paramagnetic to weak ferromagnetic phase. We find that the localized Cr 3d electrons are strongly hybridized with the valence electrons and causes spin polarization. Hence, the origin of weak ferromagnetic ordering in CrSi is due to the indirect exchange interaction between the local Cr moment via the spin polarization of the itinerant conduction electrons. During the magnetic phase transition we find that there is a change in the screening of the local Cr 3d moment by the spin polarized conduction electrons which drastically modifies the density of states. Large density of itinerant spin polarized electrons are desired for the spintronics applications, moreover the drastic variation in the density of states at the Fermi edge with temperature promises CrSi to be a potential candidate for thermoelectric applications.