Dielectric and Magnetic Properties of Sr(Fe_(1/2)Ta_(1/2))O_3 Complex Perovskite Ceramics

摘要

The dielectric and magnetic properties of Sr(Fe_(1/2)Ta_(1/2))O_3 complex perovskite ceramics were systematically investigated together with the structure. The X-ray powder diffraction analysis confirmed a Bsite disordered orthorhombic structure in space group Pbnm. Only one broadened dielectric peak with strong frequency dispersion was observed in the present ceramics, which was significantly different from that for the analogue Ba(Fe_(1/2)Nb_(1/2))O_3 and Ba(Fe_(1/2)Ta_(1/2))O_3. The strong dependence of sample thickness and electrode material indicated that the dielectric relaxation behavior at lower frequency was due to the interface effects. The present ceramics were spin glass state with slight ferromagnetic behavior below the Ne'el temperature (20 K). The co-presence of Fe~(3+) and Fe~(2+) was confirmed by the μ_(eff) value.