Dresden 2014 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

O: Fachverband Oberflächenphysik

O 37: Posters: Plasmonics, Electronic Structure and Spin-Orbit Interaction, Semiconductor and Insulator Surfaces, Nanostructures

O 37.9: Poster

Tuesday, April 1, 2014, 18:30–22:00, P2

Near-field optics of conductive ferroelectric domain walls — •Denny Lang, Susanne C. Kehr, Mathias Schröder, Alexander Haußmann, and Lukas M. Eng — IAPP, George-Bähr-Straße 1, 01069 Dresden

Ferroelectric domain walls (DWs) are planar interfaces of a few nm thickness that separate areas with different spontaneous polarizations. DWs show electric conductivity under certain conditions [1], e.g. when being illuminated by UV light, and thus are interesting as nanometer-scale optoelectronic devices [2]. We investigate the optical response of these topologically novel systems on the nm length scale by means of scattering-type scanning near-field optical microscopy (s-SNOM).

We inspect the domain wall conductivity in z-cut lithium niobate using different scanning probe methods. Firstly, we characterize the general domain structure by conventional piezoresponse force microscopy (PFM) in order to both allocate the exact DW position and quantify the magnitude of polarization in adjacent domains. Secondly, we measure the conductivity of a single DW rendered conductive by UV illumination with conductive atomic force microscopy (c-AFM). Thirdly, we study the optical response of the DW applying s-SNOM at visible and at infrared wavelengths. Here, we expect a near-field contrast since the DW constitutes a conductive singularity within a wide-bandgap insulator.

[1] M. Schröder et al., Adv. Funct. Mater. 22 (18), 3936-3944 (2012)

[2] A. Haussmann et al., Nano Lett. 9 (2), 763-768 (2009)