Physical properties of the new multiferroic perovskite-like material HoMn1−xFexO3

We report the study of the structural, magnetic and electrical properties of the multiferroic material with perovskite structure HoMn1−xFexO3 (x=0; 0.1 and 0.2) synthesized by the standard solid state reaction method. Structural analysis by X-ray diffraction (XRD) experiments shows the coexistence between two phases with the same chemical formula and with polyhedral distortions (MnO3), a phase with hexagonal symmetry (P63cm # 185) which is characteristic of the non-doped material HoMnO3 and other perovskite phase with orthorhombic symmetry (Pbnm # 62). Rietveld refinements of the experimental patterns show that the weight percentage of each phase (hexagonal or orthorhombic symmetry) depends on the degree of substitution of Fe in the Mn crystallographic sites. Measurements of polarization as a function of applied voltage at room temperature confirm a ferroelectric character for non-doped material with relative permittivity of 215.1. These measurements show that the ferroelectric behavior is deteriorated by the introduction of Fe, since in the configuration with x=0.1 (HoMn0.9Fe0.1O3) we can see ferroelectric loops with dielectric losses to small values of applied voltage and finally in the configuration with x=0.2 (HoMn0.8Fe0.2O3) the behavior is totally resistive at room temperature. Curves of magnetization as a function of temperature were carried out between 300K and 860K show an antiferromagnetic behavior in the three configurations of the HoMn1−xFexO3 material.