Conduction at domain walls in oxide multiferroics

• Published in: Nature materials Vol. 8; no. 3; pp. 229 - 234
• Main Authors: Seidel, J, Martin, L. W, He, Q, Zhan, Q, Chu, Y.-H, Rother, A, Hawkridge, M. E, Maksymovych, P, Yu, P, Gajek, M, Balke, N, Kalinin, S. V, Gemming, S, Wang, F, Catalan, G, Scott, J. F, Spaldin, N. A, Orenstein, J, Ramesh, R
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-03-2009; Nature Publishing Group
• Subjects: Biomaterials; Chemistry and Materials Science; Condensed Matter Physics; Conductivity; Electronics; Iron; Materials Science; Microscopy; Nanotechnology; Optical and Electronic Materials
• ISSN: 1476-1122; 1476-4660
• DOI: 10.1038/nmat2373

Domain walls may play an important role in future electronic devices, given their small size as well as the fact that their location can be controlled. Here, we report the observation of room-temperature electronic conductivity at ferroelectric domain walls in the insulating multiferroic BiFeO
3
. The origin and nature of the observed conductivity are probed using a combination of conductive atomic force microscopy, high-resolution transmission electron microscopy and first-principles density functional computations. Our analyses indicate that the conductivity correlates with structurally driven changes in both the electrostatic potential and the local electronic structure, which shows a decrease in the bandgap at the domain wall. Additionally, we demonstrate the potential for device applications of such conducting nanoscale features.
Domain walls may be important in future electronic devices, given their small size as well as the fact that their location can be controlled. In the case of insulating multiferroic oxides, domain walls are now discovered to be electrically conductive, suggesting their possible use in logic and memory applications.