Enhanced energy transfer between Co-dopants Pyronin-Y and Thionine incorporated into modified polymethyl methacrylate with addition of ZnO nanoparticles.

Using a prism dye cell arrangement, the study investigated spectral energy transfer between co-dopants Pyronin-Y and Thionine incorporated into ethanol-modified polymethyl methacrylate. The spectral parameters of the absorption and fluorescence spectra of the donor and acceptor dyes in the so designed solid-state dye laser were calculated theoretically. Fluorescence lasing properties and slope efficiency of the solid-state dye laser were investigated both with and without addition of ZnO nanoparticles. The dye pair generally improved lasing efficiency and tunability in the range from 582 to 689 nm.

Pulsed laser deposition and ferroelectric characterization of nanostructured perovskite lead zirconate titanate (52/48) thin films.

Perovskite lead zirconate titanate nanostructured (PZT) thin films with Zr/Ti ratio of 52/48 were deposited on Pt/TiO2/SiO2/Si(100) substrate using pulsed laser deposition method. A metal/ ferroelectric/metal (MFM) structure was used for ferroelectric property measurements, formed by depositing gold electrode on top of the film. A Nd:YAG UV laser having a wavelength of 355 nm and an energy fluence of -2.7 J/cm2 was used to deposit the film. The film was deposited on platinum (Pt) coated silicon substrate at the substrate temperature of 600 degrees C and the base vacuum of 10(-6) mbar. The scanning electron microscopy (SEM) images revealed well-crystallized films with a fine microstructure and an average grain size of - 50 nm. The ferroelectric properties of the film were studied and the results were discussed. The voltage dependent Polarization versus Electric field hysteresis measurements of PZT (52/48) pellet showed a well-defined hysteresis loop with a fairly high remnant polarization (P(r)) and low coercive field (E(c)).