Magnetization steps in the phase separated manganite La0.275Pr0.35Ca0.375MnO3

The low temperature magnetic properties of the La0.275Pr0.35Ca0.375MnO3 manganite have been investigated. Step-like charge ordered antiferromagnetic (AFM)–ferromagnetic (FM) transition is observed in the magnetic field dependence of magnetization M(H)M(H) curve below 200 K as the applied magnetic field is only several Tesla, and the magnetic step become ultrasharp at 2 K. The onset magnetic field of the step decreases initially and then increases with increasing temperatures and the critical magnetic field is sensitive to the magnetic history. The results are discussed according to the field-induced reduction of the distortion of MnO octahedron as martensitic mechanism. The magnetic phase diagram is also constructed based on the magnetic measurements.