Symmetry evolution and modulation of multiferroic characteristics in Bi1-xLaxFeO3 ceramics

The substitution of rare-earth ions has been recognized as an effective way to modify the multiferroic properties, especially to realize the electric field-controlled magnetism in BiFeO3 ceramics, in which the symmetry modulation of R3c/Pna2(1) and the unlocked ferromagnetism through breaking the cycloidal spin structure are the key issues. Here, the enhancement of ferroelectric polarization and weak ferromagnetism are investigated in Bi1-xLaxFeO3 ceramics together with the magnetoelectric coupling coefficient alpha(ME) with the development of the Pna2(1) phase. The expected electric field-controlled magnetism is achieved at the phase boundary through the electric field-induced transition of Pna2(1)/R3c, where the variation of magnetization reaches 34.18 emu/mol (58.95%) at x = 0.18 after poling. Published under an exclusive license by AIP Publishing.

Automated summary

By substituting rare-earth ions, the ferroelectric polarization and weak ferromagnetism in BiFeO3 ceramics are enhanced, achieving electric field-controlled magnetism.