Principal Investigator: Dr. Roberts Eglitis (h=24) and Dr. J. Gabrusjonoks

Project duration in years: 4 (2013-2016)

Latvian Science Council Grant No.374/2012

The project is aimed at obtaining a sound theoretical and experimental understanding of the spatial and electronic structure of ferroelectric surfaces, and how they affect the dynamics of phase transitions in mixed ferroelectrics. In order to perform the numerical calculations, we will develop the ab initio formalism for ABO3 perovskites, which would combine the advantages of both Hartree-Fock (HF) and density functional theory (DFT) approaches. Technologically prospective perovskite solid solutions like PbZrxTi1-xO3 (PZT) and KNbxTa1-xO3 (KTN), both monocrystals and thin films, will be studied for a series of compositions x. In order to interprete contradicting experimental data, we plan to calculate the atomic and electronic structure of basic electron defects called F+ and F centers, in the bulk and on the surfaces of PbTiO3, BaTiO3 and CaTiO3 perovskite oxides. We plan to study also the vacancy-vacancy interaction, and complex defects, such as dimmer F2 centers.

Published papers:

  1. R. I. Eglitis, Ab initio calculations of the atomic and electronic structure of BaZrO3 (111) surfaces, Solid State Ionics 230, p. 43-47 (2013).
  2. R. I. Eglitis and M. Rohlfing, Comparative ab initio calculations of SrTiO3 and CaTiO3 polar (111) surfaces, Phys. Stat. Sol. B, 2013 (accepted).
  3. R. I. Eglitis, Ab initio calculations of BaTiO3 (111) surfaces, Phase Transitions, 2013 (accepted).
  4. R. Jia, Z. Yi, C. Liu, H. Shi, H. Zhang and R. I. Eglitis, First principles studies of the self trapped hole and the fluorine adsorption on the SrF2 (111) surface, Computational Mater. Sci. 73, p. 9-14 (2013).