Magnetic properties of multiferroic (1-x)PbTiO₃-xDyFeO₃ system

Ceramics of a perovskite solid solution, (1-x)PbTiO₃-xDyFeO₃, with x ≤ 0.4 are synthesized using the solid-state reaction method. The linear magnetization vs. magnetic field relation as well as the Curie-Weiss type temperature dependence of magnetic susceptibility observed in compositions with x ≤ 0.2 suggests the paramagnetic nature. When x ≥ 0.25, the weak ferromagnetic state can be induced. Moreover, the Dy³⁺ ions are enrolled into the superexchange coupling together with Fe³⁺ ions at low temperature, giving rise to magnetic phase transitions upon cooling in compositions with x = 0.4. Furthermore, the paraelectric subsystem is proposed to exist in weak ferromagnetic compositions.