Subsurface Oxygen Vacancy Mediated Surface Reconstruction and Depolarization of Ferroelectric BaTiO₃ (001) Surface (Adv. Sci. 16/2025)

Surface Reconstructions In situ atomic-scale electron microscopy reveals that planar accumulation of oxygen vacancies in the subsurface TiO2 layer of vacuum-annealed ferroelectric BaTiO3 (001) surface mitigates the depolarization field by facilitating cooperative rumpling of surface and subsurface layers in a tail-to-tail dipole configuration. More details can be found in article number 2412781 by Jeehun Jeong, Jaejin Hwang, and co-workers.