Positron annihilation lifetime spectroscopy measurements identify A- and B-site cation vacancies in ferroelectric perovskite oxides (ABO3). Crystal PbTiO3 and ceramic lead zirconium titanate (PZT) were studied and gave consistent values for

the lifetime resulting from positron localization at lead vacancies VPb. Positron trapping to B-site vacancies was inferred in PZT. Temperature dependent studies showed that the defect specific trapping rate was higher for VB compared to VPb, consistent with the larger negative charge. Doping PZT with Fe increased the fraction positron trapping to VB compared to VPb-type defects.

Cation Vacancies in Ferroelectric PbTiO3 and Pb(Zr,Ti)O3 - a Positron Annihilation Lifetime Spectroscopy Study. D.J.Keeble, S.Singh, R.A.Mackie, M.Morozov, S.McGuire, D.Damjanovic: Physical Review B, 2007, 76[14], 144109 (5pp)