Paper
27 April 1993 Second-harmonic generation from liquid crystalline siloxane materials containing disperse red-1 pendant groups
Zbigniew Tokarski, Bob L. Epling, Timothy J. Bunning, Laura S. McGivern, Robert L. Crane
Author Affiliations +
Proceedings Volume 1853, Organic and Biological Optoelectronics; (1993) https://doi.org/10.1117/12.144075
Event: OE/LASE'93: Optics, Electro-Optics, and Laser Applications in Scienceand Engineering, 1993, Los Angeles, CA, United States
Abstract
A number of liquid crystalline cyclic pentamethylsiloxane compounds were synthesized containing high concentrations of covalently attached disperse red 1(4-[N-ethyl, N- hydroxyethylamino]-4'-nitroazobenzene) pendant groups. Corona poling (1.0 (mu) A/-5 kV) was used to align these pendant groups in thin films (1 - 2 micrometers ) produced by spin coating onto ITO covered glass substrates. The measured second harmonic (SH) intensities of these films were comparable to 1 mm thick, y-cut quartz. The initial rise in the SH signal at 25 degree(s)C occurred in less than 10 seconds. This was followed by an additional 20 - 50% increase in the signal over the next 1 - 15 minutes to a final equilibrium value. The SH signal of compounds in the smectic or nematic phase increased to a value of 0.7 - 1.0 X the quartz standard upon heating. An upper temperature limit for each material was observed prior to the dielectric breakdown of the film. The SH intensity typically decayed back to its prepoling value within one hour for films that were poled at 25 degree(s)C. Long term SH stability was observed in films that were poled at elevated temperatures. The intensity of the SH signal was found to be a function of the composition, liquid crystalline phase, and temperature.
© (1993) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Zbigniew Tokarski, Bob L. Epling, Timothy J. Bunning, Laura S. McGivern, and Robert L. Crane "Second-harmonic generation from liquid crystalline siloxane materials containing disperse red-1 pendant groups", Proc. SPIE 1853, Organic and Biological Optoelectronics, (27 April 1993); https://doi.org/10.1117/12.144075
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Molecules

Liquid crystals

Crystals

Liquids

Second-harmonic generation

Nonlinear optics

Glasses

Back to Top