Modeling the Dynamics of Photo-induced Reorientation of Nematic Liquid Crystals doped with Azo-dye

Abstract

We have used a continuum model of azo-dye doped liquid crystals to describe the dynamics of photo-induced enhancement of director re-orientation. By describing the dye distribution as a superposition of spherical harmonic functions we numerically integrate the dynamic equations and identify various time constants associated with cis to trans isomerization, excited state lifetime, and the various diffusion times of the different species. Our results give an experimental response time which is intensity dependent and characterized by a saturation intensity. This saturation intensity is dependent on the pump beams angle of incidence. Numerical results will be presented.

Keywords:

• dyed nematics
• modeling
• photo-induced reorientation

Acknowledgments

Acknowledgement is made to the donors of The American Chemical Society Petroleum Research Fund for partial support of this research.