X-ray magnetic circular dichroism spectroscopy investigation of ferromagnetic ordering in NdCoAsO

Recently, the electronic properties of RMOAs (R= rare earth, M = transition metal such as Fe or Co) type 3d-transition metal based layered oxypnictides have attracted considerable interest, in view of the discovery of superconductivity in the FeAs compounds. Here, we would like to present the results of ferromagnetic ordering, element specific magnetic moments of Nd and Co in NdCoAsO, obtained by x-ray magnetic circular dichroism spectroscopy at Nd and Co sites. The nature of magnetic coupling between Co and Nd and its temperature dependence in relation to the bulk magnetization will be discussed.