abstract
The crystal structure, magnetic and local ferroelectric properties of polycrystalline Bi1-xGdxFeO3 (x = 0.1, 0.2, 0.3) samples were investigated at room temperature. Gadolinium substitution was found to induce a polar-to-polar R3c -> Pn2(1)a structural phase transition at x approximate to 0.1. Increasing the content of the substituting element suppressed the spontaneous polarization in Bi1-xGdxFeO3, resulting in a ferroelectric-paraelectric Pn2(1)a -> Pnma phase transition at 0.2 < x < 0.3. The substitution caused the appearance of a weak ferromagnetic moment. The data presented are consistent with the hypothesis that the most effective way to induce spontaneous magnetization in antiferromagnetic BiFeO3 seems to be related to A-site substitution by rare-earth ions with a large difference in ionic radius with respect to Bi3+. The effect of the magnetically active Gd3+ substitution on the low-temperature magnetic properties of Bi1-xGdxFeO3 samples is also discussed. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
keywords
MAGNETIC EXCHANGE INTERACTIONS; PHASE-TRANSITIONS; BISMUTH FERRITE; SUPEREXCHANGE INTERACTION; ROOM-TEMPERATURE; THIN-FILMS; WEAK FERROMAGNETISM; PEROVSKITE; MANGANITES; STATE
subject category
Materials Science; Metallurgy & Metallurgical Engineering
authors
Khomchenko, VA; Shvartsman, VV; Borisov, P; Kleemann, W; Kiselev, DA; Bdikin, IK; Vieira, JM; Kholkin, AL
our authors
Andrei Kholkin
Principal Researcher
Joaquim Manuel Vieira
Retired Professoracknowledgements
V.A.K. is grateful to the Foundation for Science and Technology of Portugal (FCT) for financial support. P.B. is grateful to the Deutsche Forschungsgemeinschaft (DFG) for financial support through SFB 491. The work was done within the EC-funded Project