Thermomagnetization Curves and Atomic Short-Range Order for Ni-Mn Alloys

The thermomagnetization curves of Ni1-xMnx (x=0.20-0.23) alloys rapidly quenched and annealed at some conditions, in which there are variations in the atomic arrangement, were measured in order to reveal the relation between the magnetism and the atomic arrangement. The atomic short-range order parameter was determined from extended X-ray absorption fine structure (EXAFS) spectroscopy for Ni0.79Mn0.21 and Ni0.80Mn0.20 in which the short-range order cannot be obtained from X-ray diffraction technique. The magnetism of these alloys strongly depends on the number of nearest-neighbor Mn atoms around a Mn atom.