Study ofAandBsites order in lanthanide-doped lead titanate ferroelectric system

Abstract

Pb0.88Ln0.08TiO3ferroelectric system, whereLn= La, Sm, Eu, and Dy, has been characterized using Scanning Electron Microscopy, Raman spectroscopy, and X-ray diffraction experiments. Softening of the lowest transverse optical phonon modeE(1TO) was evaluated as a function of the rare earths’ ionic radius suggesting partial occupation of lanthanide ions at theAandBsites of the perovskite structure. Using Rietveld refinements, it has been established a higher incorporation of Ln3+ions into theAsites of the perovskite structure than that of theBsites for the studied ceramics. The occupation atBsites increases slightly with the decreases of the ionic radii of the lanthanides.

Resistive-like Behavior of Ferroelectric p–n Bilayer Structures Based on Epitaxial Pb(Zr0.2Ti0.8)O3 Thin Films

“…Ferroelectric materials with a perovskite structure are used in a wide variety of applications due to their multiple functional properties including the spontaneous polarization that can be manipulated with electric field, temperature, mechanical stress, and light, tunable dielectric constant, birefringence, etc. Ferroelectric layers are used in many electronic and sensing applications, such as ferroelectric field effect transistors, non-volatile ferroelectric memories (FeRAM), or pyroelectric infrared detectors. − Although there are many reports about doping in ferroelectrics, the conduction type in ferroelectric films is still a matter of debate. − The chemical formula of inorganic ferroelectric perovskites is ABO 3 , where A and B are metal atoms selected in a way such that their sum of valence electrons is +6. Further on, the discussion will be about Pb­(Zr,Ti)­O 3 (PZT) solid solutions with a Zr/Ti ratio of 20/80.…”