Thermal Relaxation Processes and Stability in Poled Electro-Optic Polymers
Abstract
We have made important progress in the last year in modeling the decay of molecular orientation in poled electro-optic materials in order to more accurately predict the evolution of the nonlinear optical response over time and are approaching a predictive description of the long time scale orientational decay of poled polymer systems. The most remarkable feature of decay measurements of the nonlinear optical response is that it appears similar over so many time scales. The breadth of the time scales involved can exceed those normally measured in dielectric relaxation measurements. Models have been developed in the dielectric literature to describe relaxation processes measured over many decades of time (or frequency). These models describe the dispersive and fractal time nature of these processes, and involve an extra parameter beyond that of a stretched exponential. Thus, one parameter defines an average time (frequency), and two describe the shape of the distribution of relaxation time (frequencies) above and below the average . An example of these models includes the Havriliak-Nagami model. We have begun to analyze our current data in light of these new models, and are developing programs to take transforms between the time and frequency domain to relate dielectric measurements to nonlinear optical.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 1994
- Accession Number
- ADA283948
Entities
People
- Kenneth D. Singer
Organizations
- Case Western Reserve University