La-doped BiFeO₃: Synthesis and multiferroic property study

Abstract

A new sol-foam-gel method was developed to fabricate La-doped BiFeO3 multiferroic materials. It was demonstrated that a gradual increase in the content of La-doped into BiFeO3 results in its structure changing from rhombohedral to orthorhombic. A study of other property changes indicates that La-doping in BiFeO3 enhances its ferromagnetism and ferroelectricity. A temperature-dependent magnetization study suggests that the magnetic property of La-doped BiFeO3 samples varied from antiferromagnetic to ferromagnetic as the content of La-doped into BiFeO3 increased from 0 to 20%. Unique temperature-dependent zero field cooling (ZFC) and field cooling (FC) magnetization behaviors were observed in 15% La-doped BiFeO3 — its ZFC temperature-dependent magnetization being ferromagnetic and its FC temperature-dependent magnetization being antiferromagnetic. A possible mechanism of such an interesting M–T behavior is discussed.