Structure and Lattice Dynamics in PLZT 8/65/35 Ceramics Irradiated by High-Current Pulsed Electron Beam.

The comprehensive study of high-current pulsed electron irradiation effect on the structure and lattice dynamics as well as optical properties of PLZT 8/65/35 ceramics have been performed. X-ray powder diffraction studies shown the transformation of the rhombohedral perovskite structure R3m (Z = 1) into orthorhombic Pmmm (Z = 1) for the sample irradiated by one pulse (dose 4 × 10¹⁴ electrons/cm²) and, as a consequence, the changes in number of phonon modes position, oscillators strength and damping in IR and Raman spectroscopy data. However neutron powder diffraction measurements of multiple irradiated samples have not been revealed any structural distortions. Dielectric parameters have shown the increasing of real and imaginary parts of complex dielectric permittivity especially in high-temperature range (T > 100°C). In the optical properties, an essential increasing of the coefficient absorption for irradiated sample in the range from 1 to 2.5 eV and the shift of the edge of fundamental absorption to lower photon energy about 0.09 eV take place. The possible mechanisms of pulsed electron irradiation effect in relaxor PLZT ceramics are discussed. [ABSTRACT FROM AUTHOR]