Ac susceptibility studies of multiferroicBiMnO3 and solidsolutions between BiMnO3 and BiScO3

Abstract

The real and imaginary parts of the ac susceptibilities of powderBiMnO3 and BiMn1−xScxO3 (x = 0.1,0.2, 0.3, 0.4, 0.5, and 0.7) samples have been measured as functions of temperature, differentdriving ac and applied dc magnetic fields, and different ac magnetic field frequencies. Bothχ′ versus T and χ′′ versus T showed strong dependence on the parameters of the ac magnetic field for ferromagnetic samplesBiMnO3 and BiMn1−xScxO3 (x = 0.1,0.2, and 0.3), indicating that the ac field interacted mainly with the domain structure. InBiMn1−xScxO3 (x = 0.1, 0.2, and 0.3), a re-entrant spin-glass transition emerged at lowtemperatures. The re-entrant spin-glass transition temperatureTRSG increased withincreasing x (TRSG = 4 Kfor x = 0.1, TRSG = 5 Kfor x = 0.2,and TRSG = 9 K for x = 0.3). For BiMn1−xScxO3 (x = 0.4,0.5, and 0.7), only the classical spin-glass transition was found (the freezing temperatureTf = 24 Kfor x = 0.4, Tf = 18 Kfor x = 0.5,and Tf = 7 K for x = 0.7) with characteristic frequency dependence of broad maxima on theχ′ versus T and χ′′ versus T curves and no dependence on the driving ac field.