Ferroelectric (FE) domain walls (DWs) have been observed in parallel alignment with surface and substrate defects since the 2000s. Now that electrically conducting FE DWs have been realized, new horizons for nanoelectronic devices approach. That is, the phenomenon now promises control over the orientation of 2D conducting channels on the nanoscale; a potential pathway for fabricating DW- mediated nanocircuits with standard lithographical techniques. Using ultrathin PbTiO3 films as a model system, we explore this mechanism with large scale density functional theory simulations on as many as 5,136 atoms. Although we expect multiple contributing factors, we show that parallel DW-ST alignment can be well explained by this configuration giving rise to an arrangement of electric dipole moments which best restore polar continuity to the film.
The paper is published in Phys. Rev. Lett. 127, 247601 (2021).
This entry was posted on 2021/12/10.