Multiferroic behavior of Aurivillius Bi4Mn3O12 from first-principles

TINTE, SILVIA; STACHIOTTI, MARCELO

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Lugar: New York; Año: 2012 vol. 85 p. 224121 - 2241126

1098-0121

The multiferroic behavior of the hypothetical Aurivillius compound Bi4Mn3O12 has been explored on the basis of density functional calculations.We find that the tetragonal paraelectric phase of this material is ferromagnetic, showing ferroelectric and antiferrodistortive instabilities similar to the ones observed in its ferroelectric parent compound Bi4Ti3O12. Our results indicate, however, that the presence of Mn+4 ions at the B sites shrinks the cell volume and, consequently, the unstable polar mode, associated with the ferroelectric polarization, is overcome by an antiferrodistortive distortion. In this way, Bi4Mn3O12 exhibits incipient ferroelectricity at its equilibrium volume. We show that the ferroelectric state can be favored by strain or partial substitution of Mn with Ti