Share Email Print
cover

Proceedings Paper

New developments in optical ordering of NLO dyes in polymers
Author(s): Michel L. Dumont
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Basic mechanisms of optical ordering processes of azo dyes in polymer matrices are now well understood. Photo-Induced Anisotropy (PIA), Photoassisted Electrical Poling (PAEP) and All-Optical Poling (AOP) are produced by an angularly selective trans-cis photoisomerization and by the angular redistribution resulting from this reversible isomerization. They differ by the symmetry of the excitation. We present new theoretical and experimental developments on this subject. Experimentally, the problem is to extend these methods to a panel of NLO molecules wider than azobenzene derivatives. Non-photoisomerizable molecules present very small effects, probably due to a selective photodegradation. A route under investigation is to build structures associating two functions: an efficient NLO function and a diazo group to stir up the polymer. Theoretically, the model for the orientation of rod-like photoisomerisable molecules is well established. We are extending it to 2D and 3D molecules, characterized by their tensorial properties and excited by light of any symmetry (particularly octupolar symmetry). The probability of excitation is formally easy to write, but the angular redistribution process and the successive photoisomerization cycles (saturation of optical pumping) modify the tensorial quantities. In AOP, the competition between centrosymmetric and non-centrosymmetric contributions is often detrimental to the building of a good (chi) .

Paper Details

Date Published: 7 December 2001
PDF: 15 pages
Proc. SPIE 4461, Linear and Nonlinear Optics of Organic Materials, (7 December 2001); doi: 10.1117/12.449827
Show Author Affiliations
Michel L. Dumont, Ecole Normale Superieure de Cachan (France)


Published in SPIE Proceedings Vol. 4461:
Linear and Nonlinear Optics of Organic Materials
Manfred Eich; Mark G. Kuzyk, Editor(s)

© SPIE. Terms of Use
Back to Top