Field-induced magnetization steps in intermetallic compounds and manganese oxides: The martensitic scenario

Field-induced magnetization jumps with similar characteristics are observed at low temperature for the intermetallic germanide ${\mathrm{Gd}}_5{\mathrm{Ge}}_4$ and the mixed-valent manganite ${\mathrm{Pr}}_{0.6}{\mathrm{Ca}}_{0.4}{\mathrm{Mn}}_{0.96}{\mathrm{Ga}}_{0.04}{\mathrm{O}}_3.$ We report that the field location—and even the existence—of these jumps depends critically on the magnetic field sweep rate used to record the data. It is proposed that, for both compounds, the martensitic character of their antiferromagnetic-to-ferromagnetic transitions is at the origin of the magnetization steps.