Optical second harmonic generation and ordering effects in the system of ferroelectric barium titanate nanocrystals

The temperature dependence of the optical second harmonic generation in nanocrystalline BaTiO3:Eu3+ revealed a strong hysteresis in the C4v–Oh ferroelectric phase transition region. The explanation of the effect by the ordering processes in the system of ferroelectric nanocrystals is confirmed by the experiments in an external electric field.