LAUSR

PbTiO3-SrTiO3 (PTO-STO) superlattice has been shown to host a variety of polarization domain structures depending on the periodicity of the superlattice. High periodicity superlattices favor a1/a2 domains, while low periodicity superlattices host flux closure domains and continuous vortices appear in between [1]. Four-dimensional scanning transmission electron microscopy (4D-STEM) and integrated differential phase contrast (iDPC) imaging have been applied extensively to study these polarization patterns [2,3]. For example, combined measurements of the polarization and electric field have shown that these vortices host regions of negative capacitance [2]. However, the atomic scale electric field in PTOSTO superlattices has yet to be investigated extensively.