Harnessing the polar vortex motion and tunable skyrmion liquid phase in oxide heterostructures

Polar topological structures such as vortices and skyrmions offer promising pathways toward low-power, high-density, and CMOS-compatible nanoelectronic devices due to their intrinsic stability, ultrasmall dimensions, and rich functional properties.1-2 However, their practical application remains limited by challenges in controlled manipulation and post-synthesis tunability. In this study, we demonstrate real-time control of polar vortices and skyrmions in PbTiO₃/SrTiO₃ superlattices using localized electric fields and thermal stimuli. Piezoresponse force microscopy (PFM) and scanning transmission electron microscopy (STEM), complemented by phase-field simulations, reveal reversible motion, reshaping, and annihilation of vortex structures, along with electric-field and temperature-dependent evolution of skyrmion phases. Correlation function analysis confirms a liquid-like skyrmion state, enabling tunable phase behavior. These findings establish a framework for dynamic control of polar topologies, advancing their integration into reconfigurable and energy-efficient topological devices.