Anisotropic Photoconduction of Triphenylene-Based DLC in Aligned Domains by Wavelength Tunable CO₂ Laser Irradiation

Abstract

Infrared induced alignment change of columnar liquid crystal domains and anisotropic electric conduction were investigated for a well-known discotic liquid crystal, 2,3,6,7,10,11-hexahexyloxytriphenylene. A uniformly aligned alignment change of domains was observed when an infrared laser corresponding to the wavelength of the aromatic C-O-C stretching vibration band was irradiated. Anisotropic photoconduction was observed for homeotropic and unidirectional planar aligned domains between in-plane two gold electrodes. Photoconductivity for unidirectional planer aligned domain was increased by 4 times compared with that for homeotropic one during dark-current was not drastically changed between two conditions.

Keywords:

• Alignment control
• discotic liquid crystal
• infrared
• triphenylene

Acknowledgment

This work is financially supported in part by the Amada Foundation for Metal Work Technology (No. AF-2009204) and the Sumitomo Science Foundation (No. 090091).