Systematic Trends in Hybrid-DFT Computations of BaTiO3/SrTiO3, PbTiO3/SrTiO3 and PbZrO3/SrZrO3 (001) Hetero Structures
Date
2022
Authors
Eglitis, Roberts I.
Piskunov, Sergei
Popov, Andrei I.
Purans, Juris
Bocharov, Dmitry
Jia, Ran
Journal Title
Journal ISSN
Volume Title
Publisher
MDPI
Abstract
We performed predictive hybrid-DFT computations for PbTiO3, BaTiO3, SrTiO3, PbZrO3 and SrZrO3 (001) surfaces, as well as their BaTiO3/SrTiO3, PbTiO3/SrTiO3 and PbZrO3/SrZrO3 (001) heterostructures. According to our hybrid-DFT computations for BO2 and AO-terminated ABO3 solid (001) surfaces, in most cases, the upper layer ions relax inwards, whereas the second layer ions shift upwards. Our hybrid-DFT computed surface rumpling s for the BO2-terminated ABO3 perovskite (001) surfaces almost always is positive and is in a fair agreement with the available LEED and RHEED experiments. Computed B-O atom chemical bond population values in the ABO3 perovskite bulk are enhanced on its BO2-terminated (001) surfaces. Computed surface energies for BO2 and AO-terminated ABO3 perovskite (001) surfaces are comparable; thus, both (001) surface terminations may co-exist. Our computed ABO3 perovskite bulk Γ-Γ band gaps are in fair agreement with available experimental data. BO2 and AO-terminated (001) surface Γ-Γ band gaps are always reduced with regard to the respective bulk band gaps. For our computed BTO/STO and PTO/STO (001) interfaces, the average augmented upper-layer atom relaxation magnitudes increased by the number of augmented BTO or PTO (001) layers and always were stronger for TiO2-terminated than for BaO or PbO-terminated upper layers. Our B3PW concluded that BTO/STO, as well as SZO/PZO (001) interface Γ-Γ band gaps, very strongly depends on the upper augmented layer BO2 or AO-termination but considerably less so on the number of augmented (001) layers. © 2022 by the authors. --//-- This is an open access article Eglitis R.I., Piskunov S., Popov A.I., Purans J., Bocharov D., Jia R., "Systematic Trends in Hybrid-DFT Computations of BaTiO3/SrTiO3, PbTiO3/SrTiO3 and PbZrO3/SrZrO3 (001) Hetero Structures", (2022) Condensed Matter, 7 (4), art. no. 70, DOI: 10.3390/condmat7040070 published under the CC BY 4.0 licence.
Description
We acknowledge the financial support from the funder—Latvian Council of Science. The funding number is: Grant No. LZP-2020/1-0345. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence, has received funding from the European Unions Horizon 2020 Framework Programme H2020-WIDESPREAD01-2016-2017-Teaming Phase2 under Grant Agreement No. 739508, project CAMART-2.
Keywords
Research Subject Categories::NATURAL SCIENCES::Physics , (001)interfaces , ABO3 perovskites , BaTiO3/SrTiO3 , SrZrO3/PbZrO3