Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
KFM: Fachverband Kristalline Festkörper und deren Mikrostruktur
KFM 13: Focus Session: (Multi-)Ferroic States III
KFM 13.6: Talk
Wednesday, March 20, 2024, 11:30–11:50, EMH 225
Charged twin domain walls in antiferroelectric-like K3[Nb3O6(BO3)2] — •Ivan N. Ushakov1, Kasper A. Hunnestad1, Christoph Grams2, Joachim Hemberger2, Petra Becker2, Ladislav Bohatý2, Thomas M. Tybell1, and Dennis Meier1 — 1Norwegian University of Science and Technology (NTNU), Trondheim, Norway — 2University of Cologne, Cologne, Germany
Antiferroelectric materials exhibit an anti-polar alignment of electric dipoles, giving rise to intriguing physical properties and functional behaviors. In this work, we apply different scanning probe microscopy techniques to image and investigate the domains and domain walls in K3[Nb3O6(BO3)2], a ferroelectric with antiferroelectric-like structure and properties. Using piezoresponse force microscopy, we show that the domains exhibit a pronounced piezoresponse, consistent with the non-centrosymmetric crystal structure. At the nanoscale, a chevron-like pattern of twin domains develops, where the crystallographic structure changes by 120∘ across the domain walls. Interestingly, we observe the formation of charged twin walls with distinctly different piezoelectric and electrostatic responses, arising from a small canted electric moment of the otherwise anti-polar arrangement of electric dipoles. Furthermore, the charged domain walls can be controlled by local electric fields. Our findings provide insight into novel types of ferroic domain walls with unusual mechanical and electronic properties.