Time dependent nature of first order antiferro–ferro magnetostructural transition in Fe0.45Rh0.45Pd0.1 alloy

Time dependence of the first order magnetostructural transition in Pd doped B2-type FeRh (Fe0.45Rh0.45Pd0.1 alloy) has been investigated. This alloy exhibits a first order ferro–antiferro magnetostructural transition at 170 K in the cooling process under a low magnetic field (0.1 T). The transition also proceeds by holding at temperatures near 170 K. In addition, we also found that the transition temperature decreases with increasing magnetic field, and the transition is suppressed under a magnetic field of 5 T or higher. Removal of the magnetic field at 4.2 K induces the magnetostructural transition, but a part of the ferromagnetic phase remains at 4.2 K. In the subsequent heating process, the remaining ferromagnetic phase (high temperature phase) transforms to the antiferromagnetic phase (low temperature phase). Such an abnormal transition implies that the first order magnetostructural transition in Fe0.45Rh0.45Pd0.1 alloy is caused by a thermal activation process.

► Magnetostructural transition of Fe0.45Rh0.45Pd0.1 alloy shows time dependence. ► The transition can be suppressed under a magnetic field of 5 T or larger. ► The suppressed phase transforms to antiferromagnetic in subsequent heating process. ► It implies that this transition is caused by thermal activation.