Magnetic circular dichroism at transition metal L_2,3 edges in D0₃-type (Fe_1-xMn_x)₃Al alloys

We have measured magnetic circular dichroism (MCD) spectra at the transition-metal L_2,3 edges in D0₃-type (Fe_1-xMn_x)₃Al in order to investigate their local magnetic moments. The analysis of the spectra shows that Fe has moments much larger than Mn, whose moment is ferromagnetically coupled with the Fe one. This does not lend support to the antiferromagnetic mechanism proposed for the reduction in magnetization as well as a large Mn moment predicted for x = 1/3. The evolution of satellites found in the Mn spectrum with x increased suggests that the change in the electronic state may result in the magnetization reduction.