| Abstract Scope |
The interplay between the polarization, charge, and strain orders within the confinement of ferroelectric heterostructures can give rise to various nanoscale polar structures such as vortices, skyrmion bubbles, and flux-closure nanodomains. These structures demonstrate fascinating static and dynamic properties that are vastly distinct from bulk ferroelectric domains. Here, by employing a dynamical phase-field model, we study the thermodynamics of the nanoscale polar structures in PbTiO3/SrTiO3 ferroelectric superlattices and their excited-state evolution dynamics during structural motion and phase transition. We simulate the unique structural response of polar vortices to an applied electric-field pulse and establish the equation of motion and the effective mass, showing good agreement with experimental measurements. We further demonstrate the light-induced formation of several hidden polar phases, resulting from the combined effects of the light-generated charge carriers and thermal energy. The present work offers theoretical guidance for exploring nanoscale polar structures and manipulating their dynamical functionalities. |