0000000000082436
AUTHOR
B. N. Mavrin
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 sho…
Mechanism of pulsed electron irradiation of the PLZT X/65/35 ceramics
The comprehensive study of high-current pulsed electron irradiation effect on the structure and lattice dynamics as well as Atomic Force (AFM) and Laser Confocal Scanning microscope (LSCM) surface imaginaries of PLZT 8/65/35 ceramics have been performed. X-ray powder diffraction studies show the transformation of the cubic perovskite Pm-3m (Z = 1) into orthorhombic Pmmm (Z = 1) structure for the sample irradiated by one pulse (dose 6 × 1014 electrons/cm2) and into cubic Pm-3m with increased lattice volume and more ordered structure at irradiating by 10 and 100 pulses (dose 6 × 1015 and 6 × 1016 el/cm2). A consequence, the changes of number, intensity and phonon modes position occur in Raman…
MICRO- AND NANO-STRUCTURES OF NOMINALLY PURE STOICHIOMETRIC LITHIUM NIOBATE SINGLE CRYSTAL IN RAMAN SPECTRA
ABSTRACT The authors show that bandwidths in Raman spectra of ferroelectric photo-refractive single crystals may depend on wavelength of laser radiation exciting the spectrum. Raman bands of lithium niobate single crystals are broader if the spectrum is excited by laser radiation in visible as compared with the spectrum excited by infrared laser radiation. Local microscopic structural heterogeneities of altered index of refraction are shown to appear in parts of the crystal under laser irradiation. Under visible radiation the structural heterogeneities provide additional contribution to broadening of Raman bands. Similar microscopic heterogeneities are practically absent at laser irradiatio…