Ferromagnetism and ferroelectricity in highly resistive Pb0.7 Sr0.3 (Fe0.012 Ti0.988) O3 nanoparticles and its conduction by variable-range-hopping mechanism

Abstract

The enhancement in ferromagnetism and ferroelectricity at room temperature for Pb0.7 Sr0.3 (Fe0.012 Ti0.988) O3 (PSFT) nanoparticles is proved by magnetization and polarization hysteresis loop. The x-ray diffraction and micrograph show that the PSFT nanoparticles have distorted tetragonal single phase, and their average particle's size is 8 nm. The effect of Sr content reduces the particle size, and hence the multiferroic system becomes more resistive, which dominates the superparamagnetic/paraelectric relaxation. The variable-range-hopping conduction mechanism explained the high resistivity of PSFT nanoparticles, which suggests that the room temperature movement of electrons involves short-range order through defect states. © 2008 American Institute of Physics.