Surface stress and lattice dynamics in oxide ultrathin films

0532118 - FZÚ 2021 RIV DE eng J - Journal Article
Premper, J. - Schumann, F.O. - Dhaka, A. - Polzin, S. - Kostov, K.L. - Goian, Veronica - Sander, D. - Widdra, W.
Surface stress and lattice dynamics in oxide ultrathin films.
Physica Status Solidi B. Roč. 257, č. 7 (2020), s. 1-10, č. článku 1900650. ISSN 0370-1972. E-ISSN 1521-3951
Institutional support: RVO:68378271
Keywords : epitaxial growth * oxide thin films * perovskites * surface phonons * surface stress
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.710, year: 2020
Method of publishing: Open access

The lattice misfit between the substrate and an epitaxial film leads in general to static forces, which define the interface stress, and dynamic responses that modify the thin‐film lattice dynamics. Within the class of binary oxides, NiO(001) grown on Ag(001) is chosen, which exhibits a −2.2% lattice mismatch, and BaO(001) on Pt(001), a system with a negligible lattice mismatch. For the ternary oxides, perovskite thin films of BaTiO3 grown epitaxially on Pt(001) with a lattice mismatch of −2.3% are focused upon. The surface stress experiments are conducted with an optical two‐beam curvature technique under in situ growth conditions. Surface and thin‐film phonons are determined by high‐resolution electron energy loss spectroscopy. Surface stress and lattice dynamics are discussed in the range from the oxide monolayer to thin films of about 20 unit cell in thickness.
Permanent Link: http://hdl.handle.net/11104/0310720