Manifestation of ferroelectromagnetism in multiferroic BiMnO3

Multiferroic ${\mathrm{BiMnO}}_3$ with a highly distorted perovskite structure induced by the stereochemically active $6s^2$ electron lone pairs of ${\mathrm{Bi}}^{3+}$ was synthesized at a high pressure of 6 GPa. Magnetization, differential scanning calorimetry, dielectric permittivity, and in situ powder x-ray diffraction as a function of temperature were carried out, respectively. In light of comprehensive evaluation, we can conclude that the synthetic ${\mathrm{BiMnO}}_3$ ceramic displays ferromagnetic and ferroelectric orderings simultaneously, i.e., ferroelectromagnetism below its ferromagnetic Curie temperature $T_M\sim 100\mathrm{K}$ .