Second-order nonlinearity of NaNbO3 nanocrystals with orthorhombic crystalline structure

Abstract

Abstract Orthorhombic sodium niobate (NaNbO3) nanocrystals, transparent in the visible and near-infrared, were synthesized by using the Pechini s sol-gel method. Experiments were performed to measure the first hyperpolarizability of the nanoparticles by using a pulsed laser operating at 1064\u202fnm. The hyper-Rayleigh scattering technique was used to analyze the second harmonic scattered light generated by the nanocrystals. By using the external reference method, with para-nitroaniline as the standard reference, we determined the NaNbO3 hyperpolarizability per nanoparticle volume (0.93\u202f×\u202f10−29\u202fesu/nm3) for the first time, and show that the effective second-order susceptibility has the same order-of-magnitude as LiNbO3 and KNbO3 nanocrystals.