Impurity Effects and Charge Transport in ABO(3) Single Crystal Oxides: Photorefractivity-Oriented and Basic Studies

Non linear optical, dielectric, magnetic properties of ABO3 single crystal oxides let the implementation of acousto-optic, electro-optic, photonic, spintronic devices. In particular, significant role is played by the ferroelectric and photorefractive materials, where the photo-induced change in refractive indexes requires charge transport and impurities which support charge transfer, space charge formation and localization with accompanying electric field. Besides, ABO3 paraelectric perovskites regularly reveal newel effects connected with charge transport, e.g., photo-induced polar state recently reported for SrTiO3 and KTaO3. In this work we review our recent investigation, pointing out our studies of photo-transport in SrTiO3, Cu-doped KTaO3 and LiNbO3:Hf.