Controlled charging of ferroelastic domain walls in oxide ferroelectrics

by Xian-Kui Wei, Tomas Sluka, Barbara Fraygola, Ludwig Feigl, Hongchu Du, Lei Jin, Chun-Lin Jia and Nava Setter

Conductive domain walls (DWs) in ferroic oxides as device elements are a highly attractive research topic because of their robust and agile response to electric field. Charged DWs possessing metallic-type conductivity hold the highest promises in this aspect. However, their intricate creation, low stability, and interference with nonconductive DWs hinder their investigation and the progress toward future applications.

In the present study, it is demonstrated that conversion of the nominally neutral ferroelastic 90° DWs into partially charged DWs in Pb(Zr0.1Ti0.9)O3 thin films enables easy and robust control over the DW conductivity. By employing transmission electron microscopy, conductive atomic force microscopy and phase-field simulation, it is revealed that charging of the ferroelastic DWs is controlled by mutually coupled DW bending, type of doping, polarisation orientation and work-function of the adjacent electrodes. Particularly, the doping outweighs other parameters in controlling the DW conductivity. Understanding the interplay of these key parameters not only allows to control and optimise conductivity of such ferroelastic DWs in the oxide ferroelectrics but also paves the way for utilisation of DW-based nanoelectronic devices in the future.

Further reading:

Xian-Kui Wei, Tomas Sluka, Barbara Fraygola, Ludwig Feigl, Hongchu Du, Lei Jin, Chun-Lin Jia and Nava Setter:
Controlled charging of ferroelastic domain walls in oxide ferroelectrics,
ACS Appl. Mater. Interfaces 9 (2017) 6539