Magnetization sign reversal, exchange bias, and Griffiths-like phase in orthorhombic perovskite Pr2FeMnO6

The perovskite Pr2FeMnO6 has been synthesized by citrate-gel combustion method. The material has an orthorhombic crystal structure with Pbnm space group. The presence of Fe3+ and Mn3+ cations in the material are confirmed by XPS analysis. A magnetization sign reversal is observed for the material at low-temperatures in low applied magnetic fields. When the applied field or temperature is increased, the negative magnetization got diminished. Such a sign reversal of magnetization is observed for the material as a result of the interaction between components of paramagnetic Pr3+ and Mn3+ moments opposite to the component of the ferromagnetic Fe3+ moment or the anti-aligned Fe-rich regions to that of Mn-rich regions containing with Pr3+. Negative exchange bias is also exhibited by Pr2FeMnO6 below 200 K which can be ascribed to the Dzyaloshinskii-Moriya interaction and magnetic exchange anisotropy. A high-temperature magnetic transition at T-C = 576 K is identified for the material from the thermomagnetic data. From the detailed analysis of the thermomagnetic data, the presence of ferromagnetic short-range correlations is observed far above the T-C, which suggests a Griffiths-like phase with Griffiths temperature at T-G = 681 K.