Ferroelectric and dielectric properties of ferroelectromagnet Pb(Fe1/2Nb1/2)O3 ceramics and thin films

The ferroelectric and dielectric properties of ferroelectromagnet Pb(Fe1/2Nb1/2)O-3 (PFN) ceramics and thin films prepared by pulsed laser deposition (PLD) have been investigated systematically. PFN ceramics experienced a para-ferroelectric transition and a para-antiferromagnetic transition at 380 K and 145 K, respectively. At room temperature, it has an electrical remnant polarization of 11.5 mu C/cm(2) and a coercive field of 4.04 kV/cm. The dielectric behaviors show characteristics of diffusive phase transition at a wide temperature range around 380 K. Anomalies in the dielectric constant and loss tangent have been observed near the Neel temperature of 145 K, indicating a coupling between the ferroelectric and antiferromagnetic orders in PFN ceramics. At room temperature, the PFN films exhibited a remnant electric polarization of 7.4 mu C/cm(2), a coercive field of 10.5 kV/cm, and a dielectric constant of 486 at frequency of 10 kHz, indicating their potential applications in memory devices. (C) 2000 Kluwer Academic Publishers.