Optical/ferroelectric characterization of BaTiO3 and PbTiO3 colloidal nanoparticles and their applications in hybrid materials technologies.

In this paper, we will explore how optical and ferroelectric properties of the stressed ferroelectric nanoparticles prepared through ball milling set a limit on the performance of optical and electro-optical devices based on such materials. It was found that suspensions of BaTiO3 nanoparticles exhibit a blue shift in the optical band gap with a decrease in particle size. The optical band gap of PbTiO3 nanoparticles is not affected by the milling time. Polarization switching is composed of slow and fast components. A slow component is threshold-less and is caused by the particle reorientation while a fast component has a threshold, and its rise time is inversely proportional to the electric field. The absorption edge of these suspensions accounts for the applications in the near UV range, while kinetics of the polarization switching governs the speed of electro-optical devices.