Hyper-Rayleigh scattering from BaTiO3 and PbTiO3 nanocrystals

The hyper-Rayleigh scattering technique was applied to measure the first-order hyperpolarizability, β, of ferroelectric BaTiO3 and PbTiO3 nanoparticles (NPs) dissolved in methanol. The crystalline particles have average diameter of ≈50 nm as determined by scanning electron microscopy. A 8 ns pulsed laser operating at 1064 nm was used as the excitation source to generate the second harmonic scattered light. The results show that the per nanoparticle β value is 10−24 esu and the β value per unit volume of NPs is two orders of magnitude larger than that observed for antiferroelectric NaNbO3 nanoparticles.