Ferroelectric domain structure of anisotropically strained NaNbO{sub 3} epitaxial thin films

Journal Article · Wed May 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4876906· OSTI ID:22304323

Braun, D.; Schmidbauer, M.; Duk, A. ^[1]; Wördenweber, R. ^[2]

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1. Leibniz-Institute for Crystal Growth, Max-Born-Str. 2, 12489 Berlin (Germany)
2. Forschungszentrum Jülich, Peter Grünberg Institute, Jülich (Germany)

NaNbO{sub 3} thin films have been grown under anisotropic biaxial strain on several oxide substrates by liquid-delivery spin metalorganic chemical vapor deposition. Compressive lattice strain of different magnitude, induced by the deposition of NaNbO{sub 3} films with varying film thickness on NdGaO{sub 3} single crystalline substrates, leads to modifications of film orientation and phase symmetry, which are similar to the phase transitions in Pb-containing oxides near the morphotropic phase boundary. Piezoresponse force microscopy measurements exhibit large out-of-plane polarization components, but no distinctive domain structure, while C-V measurements indicate relaxor properties in these films. When tensile strain is provoked by the epitaxial growth on DyScO{sub 3}, TbScO{sub 3}, and GdScO{sub 3} single crystalline substrates, NaNbO{sub 3} films behave rather like a normal ferroelectric. The application of these rare-earth scandate substrates yields well-ordered ferroelectric stripe domains of the type a{sub 1}/a{sub 2} with coherent domain walls aligned along the [001] substrate direction as long as the films are fully strained. With increasing plastic lattice relaxation, initially, a 2D domain pattern with still exclusively in-plane electric polarization, and finally, domains with in-plane and out-of-plane polar components evolve.

• OSTI ID: 22304323
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 20; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
CHEMICAL VAPOR DEPOSITION
DOMAIN STRUCTURE
EPITAXY
FERROELECTRIC MATERIALS
MODIFICATIONS
MONOCRYSTALS
NIOBATES
OXIDES
PHASE TRANSFORMATIONS
POLARIZATION
RARE EARTHS
SODIUM COMPOUNDS
SPIN
STRAINS
SUBSTRATES
SYMMETRY
THICKNESS
THIN FILMS