Charge transport in epitaxial barium titanate films

0539019 - FZÚ 2021 RIV US eng J - Journal Article
Tyunina, Marina - Savinov, Maxim
Charge transport in epitaxial barium titanate films.
Physical Review B. Roč. 101, č. 9 (2020), s. 1-8, č. článku 094106. ISSN 2469-9950. E-ISSN 2469-9969
R&D Projects: GA ČR(CZ) GA19-09671S; GA MŠMT(CZ) EF16_019/0000760
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : thin-films * oxygen vacancies
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 4.036, year: 2020
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevB.101.094106

The electrical conductivity of epitaxial BaTiO3 films was studied by small-signal impedance spectroscopy at temperatures of 10–720 K using Pt-BaTiO3-SrRuO3 capacitors. The ∼150-nm-thick BaTiO3 films possessed different lattice strains and degrees of oxygen deficiency. A crossover between the low-temperature hopping of small polarons and the high-temperature semiconductor- to metal-type behavior was demonstrated in all films. It was suggested that the small electron polarons originate from self-trapping at Ti in the stoichiometric tensilestrained film and from trapping at Ti next to the oxygen vacancy in the oxygen-deficient films. The conductionband transport was ascribed to the thermally activated release of the trapped electrons. It was pointed out that the electronic release can mimic the motion of oxygen vacancies, which are actually immobile.
Permanent Link: http://hdl.handle.net/11104/0316763