Variable Energy Positron Annihilation Spectroscopy of Perovskite Oxides

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The application of variable energy positron annihilation spectroscopy (VE-PAS) methods to the study of perovskite oxide, ABO3, material thin films and near-surface regions is reviewed. The primary focus is on ferroic perovskite titanate oxide materials SrTiO3 and Pb (ZrxTi1-x)O3, but studies of BaTiO3, LaxSr1-xCoO3, La0.67Sr0.33MnO3 and YBa2CuO7-δ are also included. Characterization of single layer and multilayer structures is discussed. The methods, in particular positron annihilation lifetime spectroscopy, allow the identification of cation vacancy defects at both the A-and B-sites with parts per million sensitivity. Varying oxygen deficiency is often observed to result in marked changes in PAS spectra; these effects are reviewed and discussed.

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B.N. Ganguly and G. Brauer

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201-233

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D. J. Keeble, "Variable Energy Positron Annihilation Spectroscopy of Perovskite Oxides", Defect and Diffusion Forum, Vol. 331, pp. 201-233, 2012

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