Theoretical Studies of Nonlinear Optical Properties of Conjugated Polymers
Abstract
The study of the non-linear optical properties of polymeric systems is a challenging and exciting field of research ranging from device engineering, optical measurements, chemical synthesis to design and theoretical issues. At the present time, most of the basic science needed for the synthesis of molecules and the design of devices utilizing second order optical susceptibilities is in hand, although certain issues remain to be resolved. On the other hand, many important questions regarding the design and use of third order optical susceptibilities are still unanswered. The earliest ideas of the importance of low dimensionality optical band gaps suggests the use of conjugated molecules. At present, there is considerable effort, both experimentally and theoretically, in optimizing the value of gamma for polymers or oligomers with conjugated segments, because such conjugated polymers (like polyacetylene, polythiophenes, and the poly-diacetylenes) have very large gamma. These polymers have also been under intense scrutiny because of their large conductivities when doped. Although we are beginning to understand the theoretical reasons for the various unusual properties of the materials, we do not understand the factors that limit the ultimate value of gamma. For example, what are the important structures and interactions in the molecule the prevent gamma from being as large as possible while still having a small absorption coefficient, and how can we design molecules with these constraints in mind.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 21, 1993
- Accession Number
- ADA267390
Entities
People
- Robert J. Silbey
Organizations
- Massachusetts Institute of Technology