Diffuse X-ray scattering from 180° ferroelectric stripe domains: polarization-induced strain, period disorder and wall roughness

Alexandre Boulle (1) , Infante Ingrid C. (2) , Nathalie Lemee (3)

1 SPCTS-AXE3 - Axe 3 : organisation structurale multiéchelle des matériaux
2 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides
3 LPMC - Laboratoire de Physique de la Matière Condensée

A key element in ferroic materials is the presence of walls, separating domains with different orientations of the order parameter. We demonstrate that 180° stripe domains in ferroelectric films give rise to very distinct features in their diffuse X-ray scattering (DXS) intensity distributions. A model is developed that allows to determine not only the domain period but also the period disorder, the thickness and roughness of the domain walls, and the strain induced by the rotation of the polarization. As an example, the model is applied to ferroelectric/paraelectric superlattices. Temperature-dependent DXS measurements reveal that the polarization-induced strain dramatically decreases with increasing temperature and vanishes at the Curie temperature. The motion of ferroelectric domain walls appears as a collective process that does not create any disorder in the domain period, whereas the pinning by structural defects increases the wall roughness. This work will facilitate in-situ quantitative studies of ferroic domains and domain wall dynamics under the application of external stimuli, including electric fields and temperature.

Domaines: Matériaux

Alexandre Boulle, Infante Ingrid C., Nathalie Lemee. Diffuse X-ray scattering from 180° ferroelectric stripe domains: polarization-induced strain, period disorder and wall roughness. Journal of Applied Crystallography, 2016, 49 (3), pp.845-855. ⟨10.1107/S1600576716005331⟩. ⟨hal-02193208⟩