Effect of high-energy heavy ion irradiation on magnetic properties of Ni-Mn alloys

Both ordered and disordered Ni-Mn alloys have been irradiated with 230 MeV-Xe ions up to the fluence of 1014 ions/cm2 using a tandem accelerator. No significant changes have been observed in 80 at.% Ni-Mn alloy in either ordered or disordered state. However, the Curie temperature and the spin glass transition temperature of ordered 75 at.% Ni-Mn alloy decreased significantly by the irradiation. These results can be explained by considering the atomic disordering by the irradiation.