Domain wall conductivity in semiconducting hexagonal ferroelectric TbMnO₃ thin films

Authors

D. J. Kim, University of Nebraska - Lincoln
J. G. Connell, University of Kentucky
S. S. A. Seo, University of Kentucky
Alexei Gruverman, University of Nebraska-LincolnFollow

Date of this Version

2016

Citation

Nanotechnology 27 (2016) 155705 (6pp)

Comments

© 2016 IOP Publishing Ltd

Abstract

Although enhanced conductivity of ferroelectric domain boundaries has been found in BiFeO₃ and Pb(Zr,Ti)O₃ films as well as hexagonal rare-earth manganite single crystals, the mechanism of the domain wall conductivity is still under debate. Using conductive atomic force microscopy, we observe enhanced conductance at the electrically-neutral domain walls in semiconducting hexagonal ferroelectric TbMnO₃ thin films where the structure and polarization direction are strongly constrained along the c-axis. This result indicates that domain wall conductivity in ferroelectric rare-earth manganites is not limited to charged domain walls. We show that the observed conductivity in the TbMnO₃ films is governed by a single conduction mechanism, namely, the back-to-back Schottky diodes tuned by the segregation of defects.