Magnetism of La_0.875Sr_0.125MnO₃ by means of magnetometry and XMCD

The manganites La_1-xSr_xMnO₃ exhibit a remarkable rich phase diagram as function of temperature, doping concentration and magnetic field, accompanied by attractive properties like colossal magneto resistance (CMR). Furthermore lightly doped La_1-xSr_xMnO₃ (around x = 0.125) shows an unusual ferromagnetic insulating (FMI) ground state which can not be explained by the conventional double exchange model. We studied the magnetic properties of a La_0.875Sr_0.125MnO₃ single crystal by means of temperature dependent magnetometry and applied x-ray circular magnetic dichroism (XMCD) at the Mn L_2,3 edges. In contrast to previous results reported [1] we do not find a significant Mn orbital moment, neither in the FMI phase (T < 180 K) nor in the high temperature paramagnetic insulating phases (T > 180 K). The experimental XMCD results are compared with charge transfer multiplet calculations.