Pr2FeCrO6: A Type I Multiferroic

Abstract

We synthesized double perovskite Pr₂FeCrO₆ by solid-state method. Analysis of its X-ray powder diffraction shows that the compound crystallizes in a centrosymmetric structure with space group Pbnm. Our X-ray photoelectron spectroscopy (XPS) studies show that all the cations are present in +3 oxidation state. Magnetization studies of Pr₂FeCrO₆ show that the material is paramagnetic at room temperature and undergoes a magnetic transition below T_CM = 250 K. We observe clear magnetic hysteresis loop, for example, below 150 K. A low remnant magnetization M_r, ∼0.05 μ_B/f. u., is inferred from the observed magnetic hysteresis loop. ⁵⁷Fe Mössbauer study at 25 K shows a high hyperfine magnetic field of ∼53 T at the Fe nucleus, which corresponds to a magnetic moment of ∼6-7 μ_B/Fe. These two results together suggest a ferrimagnetic (nearly compensated or canted) ordering of the Fe moments. Mössbauer studies close to the ferrimagnetic ordering temperature suggest interesting magnetic relaxation effects. A dielectric anomaly observed at T_CE = 453 K signals a ferroelectric ↔ paraelectric phase transition. We observe at room temperature a clear and well-defined ferroelectric hysteresis loop, P_S = 1.04 μC/cm², establishing ferroelectricity in the material. From these results, we conclude that Pr₂FeCrO₆ is a type I multiferroic (T_CE > T_CM).