Compression mechanisms of ferroelectric PbTiO via high pressure neutron scattering.

Switchable atomic displacements generate electric dipole moments in ferroelectric materials utilized in many contemporary devices. Lead titanate, a perovskite oxide with formula PbTiO, has been referred to as a textbook example of a prototype displacive ferroelectric and is a testing platform of widely used models of piezoelectric response of complex solid-solutions. PbTiO has been addressed by experimental and computational studies, often with apparently conflicting conclusions.

Raman Study of the Structural Distortion in the Ni1-xCoxTiO3 Solid Solution.

Raman spectra were collected on Ni1-xCoxTiO3 (0 ≤ x ≤ 1) ilmenite samples as a function of the temperature between 4 and 1200 K. An evident symmetry lowering from the prototype R3̅ symmetry is observed. The distortion was largest for the x = 0.

Phase transitions and thermal-stress-induced structural changes in a ferroelectric Pb(Zr0.80Ti0.20)O3 single crystal.

A single crystal of lead-zirconate-titanate, composition Pb(Zr0.80Ti0.20)O3, was studied by polarized-Raman scattering as a function of temperature.

Microstrain in tetragonal lead-zirconate-titanate: the effect of pressure on the ionic displacements.

Piezoelectric materials respond to external stimuli by adjusting atomic positions. In solid-solutions, the changes occurring in atomic scale are very complex since the short- and long-range order are different. Standard methods used in diffraction data analysis fail to model the short-range order accurately.

Pressure-induced reversal between thermal contraction and expansion in ferroelectric PbTiO3.

Materials with zero/near zero thermal expansion coefficients are technologically important for applications in thermal management and engineering. To date, this class of materials can only be produced by chemical routes, either by changing chemical compositions or by composting materials with positive and negative thermal expansion. Here, we report for the first time a physical route to achieve near zero thermal expansion through application of pressure.