Ion-species dependence of swift heavy ion-induced ferromagnetism of Fe–50at.%Rh alloy at low temperatures

Fe–50at.%Rh alloys were irradiated with 120 MeV 58Ni, 150 MeV 86Kr, 200 MeV 136Xe and 200 MeV 197Au ions at room temperature. Effects of the ion irradiation on magnetic properties of the alloy were investigated by using superconducting quantum interference device (SQUID). We have observed that the swift heavy ion irradiation induces the ferromagnetic state in Fe–50at.%Rh even at 20 K, and the resulting magnetization strongly depends on ion-species and ion-fluence. We discuss the relationship between the swift heavy ion-induced ferromagnetism of Fe–50at.%Rh alloy and the energy deposited in the Fe–Rh alloys through electronic excitation and elastic collision processes.