Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DF: Fachverband Dielektrische Festkörper

DF 1: Focus Session: Conductive Domain Walls

DF 1.3: Topical Talk

Montag, 26. März 2012, 10:30–10:50, EB 107

UV-induced domain wall conductivity in Lithium Niobate single crystals — Mathias Schröder, •Alexander Haußmann, and Lukas M. Eng — Institute of Applied Photophysics, Technische Universität Dresden, D-01062 Dresden, Germany

For the last years, electronic conduction at ferroelectric domain walls (DWs) in thin films has triggered extensive research activities regarding possible nanoelectronic applications [1,2,3]. Here, we show that this effect is not restricted to thin film systems, but can be observed in highly insulating bulk single crystals as well, according to theoretical predictions [4]. In ferroelectric lithium niobate, DW conductivity can be switched and adjusted by super bandgap illumination (λ ≤ 310 nm) within a broad intensity range at room temperature. Furthermore, we demonstrate that this photo-induced DW conductivity can be elegantly tuned by engineering the tilting angle of the DWs with respect to the polar axis. Our experimental results were obtained using conductive atomic force microscopy (c-AFM) under UV illumination to map the DW conductivity with a resolution in the nm range.

[1] J. Seidel et al. Nat. Mater. 8, 229 (2009).

[2] S. Farokhipoor et al. Phys. Rev. Lett. 107, 127601 (2011).

[3] J. Guyonnet et al. Adv. Mater. 23, 5377 (2011).

[4] M. Y. Gureev et al., Phys. Rev. B 83, 184104 (2011).