Domain wall state diagram for SrTiO_(3)/BaTiO_(3) superlattice structures

The domain wall structure of ferroelectric/paraelectric superlattices can be much more complex due to the influence of the superlattice stacking structure,the in-plane strain induced by the substrate and environmental temperature.In this study,we employed a phase field model to investigate the domain wall state of the SrTiO_(3)/BaTiO_(3) superlattice structure.The domain wall thickness for the SrTiO_(3)/BaTiO_(3) layer was measured using a hyperbolic function.Based on the simulation results,here,we show a domain wall state diagram to distinguish the hard and soft domain states.The polarization profiles across hard/soft domain walls were illustrated and analyzed.Our simulation results offer a useful concept for the control of the domain wall state in the ferroelectric superlattice.