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07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
9.3K
Polarization driven conductance variations at charged ferroelectric domain walls
A-S Pawlik1, T Kämpfe, A Haußmann
1IFW-Dresden, Helmholtzstr. 20, 01069 Dresden, Germany. a.koitzsch@ifw-dresden.de.
Nanoscale
|July 22, 2017
Summary
Conducting domain walls (CDWs) in lithium niobate were characterized using advanced microscopy. Their local conductance is quantitatively linked to the domain wall inclination angle, aiding optoelectronic device development.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Conducting domain walls (CDWs) in ferroelectric materials offer potential for nanoscale optoelectronic devices.
- Characterizing microscopic properties of CDWs is challenging due to their small size and insulating nature.
Purpose of the Study:
- To investigate individual CDWs in single-crystalline LiNbO3.
- To explore the relationship between local conductance and domain wall properties.
Main Methods:
- Combined use of photoemission electron microscopy (PEEM) and second harmonic generation (SHG) microscopy.
- PEEM for local conductance mapping; SHG for domain wall inclination angle (α).
Main Results:
- SHG microscopy revealed the domain wall inclination angle α.
- PEEM provided sensitive local conductance measurements.
- A quantitative correlation between local conductance and α was established, supporting theoretical predictions.
Conclusions:
- Local conductance of CDWs in LiNbO3 is dictated by their inclination angle α.
- PEEM is a valuable non-contact tool for mapping conductance in resistive materials.
- Findings advance understanding of CDW electronic structure for device applications.
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