Rotational polarization topologies at the nanoscale have been observed by means of scanning transmission electron microscopy in BaTiO3/SrTiO3 superlattices grown on cubic SrTiO3(001). The transition from a highly homogeneous polarization state to rotational nanodomains is achieved by controlling the superlattice period while maintaining compressive epitaxial strain. The nanodomains prove that nominal tetragonal structure of BaTiO3 allows rotational polar textures.
Rotational Polarization Nanotopologies in BaTiO3/SrTiO3 Superlattices
Saúl Estandía, Florencio Sánchez, Matthew F. Chisholm, Jaume Gázquez
Nanoscale 11, 21275-21283, 2019
Figure: Scanning transmission electron microscopy HAADF image (left panel) of a 6x (10 u.c. BaTiO3)/(10 u.c. SrTiO3) superlattice and corresponding dipoles map (right panel). Marked regions are zoomed in the bottom images (without angle colour map).