Properties of rare-earth scandate single crystals (Re=Nd−Dy)

Section: Discussionmentioning

confidence: 87%

Ferroelectric nanodomains in epitaxial PbTiO3 films grown on SmScO3 and TbScO3 substrates

Borodavka

Gregora

Bartasyte

et al. 2013

“…Furthermore, literature values are used for the lattice parameters and thermal expansion coefficients of the film and substrates. 39 The resulting predictions for the critical thicknesses h c due to dislocation formation are 11.1 nm, 9.6 nm, and 5.9 nm for SrTiO 3 grown on DyScO 3 , TbScO 3 , and GdScO 3 , respectively, along the large strain directions. Similarly, the critical thickness can be calculated for the other samples and for the small strain direction of SBTO.…”

Section: Resultsmentioning

confidence: 97%

Engineering of the Curie temperature of epitaxial Sr1−xBaxTiO3 films via strain

Dai

Schubert

Hollmann

et al. 2016

Articles you may be interested inEffect of crystal orientation on the phase diagrams, dielectric and piezoelectric properties of epitaxial BaTiO3 thin films AIP Advances 6, 015309 (2016) (110) substrates is presented. X-ray diffraction measurements demonstrate that all films are grown epitaxially. The tensile in-plane strain is only partially compensated by a contraction of the out-of-plane lattice parameter. As a result, the volume of the unit cell of the Sr 1Àx Ba x TiO 3 film increases due to the tensile strain, and the resulting Poisson ratio of the film is % 0.33, which is larger than but still close to the literature values of % 0.23 for unstrained defect-free SrTiO 3 . The Curie temperature derived from the temperature dependence of the in-plane dielectric response leads to a straintemperature phase diagram for the epitaxial Sr 1Àx Ba x TiO 3 films. The experimental data show a deviation from the linear dependence predicted by the Landau thermodynamic theory for large strain (>1.2%). However, using the equilibrium thermodynamic analysis, we can demonstrate that this deviation arises from the relaxation of the strain due to defect formation in the film. The result reveals that in addition to the nominal misfit strain, the defect formation strongly affects the effective strain and, thus, the dielectric response of epitaxially grown ferroelectric films. Published by AIP Publishing.[http://dx

“…where a sub and a sup are the lattice pseudo cubic lattice constants 43 and superlattices, shown in Table I. Figure 2 compares the amplitude images of [(BaTiO 3 ) n / (SrTiO 3 ) m ] p superlattices grown on the three substrates, and Fig.…”

Section: Experimental and Theoretical Proceduresmentioning

confidence: 99%

Direct determination of the effect of strain on domain morphology in ferroelectric superlattices with scanning probe microscopy

Kathan-Galipeau

et al. 2012

. (2012). Direct determination of the effect of strain on domain morphology in ferroelectric superlattices with scanning probe microscopy. Journal of Applied Physics, 112(5) AbstractA variant of piezo force microscopy was used to characterize the effect of strain on polarization in [(BaTiO 3 ) n /(SrTiO 3 ) m ] p superlattices. The measurements were compared to theoretical predictions based on phase-field calculations. When polarization is constrained to be perpendicular to the substrate, the measured polarization and domain morphology agree quantitatively with the predictions. This case allows the presence of an internal electric field in the thin film to be identified. The measured trend in piezoelectric response with strain state was in qualitative agreement with predictions, and the differences were consistent with the presence of internal electrical fields. Clear differences in domain morphology with strain were observed; and in some cases, the lateral anisotropic strain appeared to influence the domain morphology. The differences in magnitude and morphology were attributed to the internal electric fields and anisotropic strains. A variant of piezo force microscopy was used to characterize the effect of strain on polarization in [(BaTiO 3 ) n /(SrTiO 3 ) m ] p superlattices. The measurements were compared to theoretical predictions based on phase-field calculations. When polarization is constrained to be perpendicular to the substrate, the measured polarization and domain morphology agree quantitatively with the predictions. This case allows the presence of an internal electric field in the thin film to be identified. The measured trend in piezoelectric response with strain state was in qualitative agreement with predictions, and the differences were consistent with the presence of internal electrical fields. Clear differences in domain morphology with strain were observed; and in some cases, the lateral anisotropic strain appeared to influence the domain morphology. The differences in magnitude and morphology were attributed to the internal electric fields and anisotropic strains. Disciplines Materials Science and Engineering