Structural and magnetic properties of Si-doped Ni3Mn alloys

The structural and the magnetic properties of some (Ni3-xSix)Mn alloys (wit h 0.03 less than or equal to x less than or equal to 0.10) have been invest igated by using neutron and X-ray diffraction, vibrating sample magnetometr y, and the ac susceptibility in the temperature range of 2 similar to 300 K . After zero-field cooling down to 2 K, the magnetization with increasing t emperature passes through a maximum at around 85 K. With decreasing tempera ture and field cooling it continues to rise beyond the value of the zero-fi eld cooling maximum and gradually levels out. All the samples displayed hys teresis loops that were displaced from the origin after field cooling. The ac susceptibilities all showed a broad maximum at around 110 K, indicating re-entrant spin glass behavior. Neutron and X-ray diffraction confirmed the alloys to be single phases with a face-centered cubic structure. Neutron d iffraction showed evidence that the magnetic properties of the alloys were influenced by atomic short-range order, particularly for x=0.07.