Effect of Gd substitution on the crystal structure and multiferroic properties of BiFeO3

Abstract The crystal structure, magnetic and local ferroelectric properties of polycrystalline Bi 1− x Gd x FeO 3 ( x = 0.1, 0.2, 0.3) samples were investigated at room temperature. Gadolinium substitution was found to induce a polar-to-polar R 3 c → Pn 2 1 a structural phase transition at x ≈ 0.1. Increasing the content of the substituting element suppressed the spontaneous polarization in Bi 1− x Gd x FeO 3 , resulting in a ferroelectric–paraelectric Pn 2 1 a → Pnma phase transition at 0.2 x 3 seems to be related to A-site substitution by rare-earth ions with a large difference in ionic radius with respect to Bi 3+ . The effect of the magnetically active Gd 3+ substitution on the low-temperature magnetic properties of Bi 1− x Gd x FeO 3 samples is also discussed.