Application Of A New Method Of The Determination Of Electro-Optic Constants To Poled Polycarbonate Doped With Organic Molecules, Polydiacetylene And Other Polymer Films

Shinji Fukaya,Akikatsu Ueki,Garo Khanarian,Takayoshi Kobayashi,Kaoru Minoshima,Shintaro Nomura

doi:10.1117/12.962123

Abstract

The measurement of electro-optic (EO) constants of three groups of materials using samples in a Fabry-Perot (FP) cavity composed of two metal mirrors which are utilized also as electrodes is reported. Firstly, the linear (Pockels) and quadratic (Kerr) EO effects of poled polymers doped with organic molecules were studied. The sample used was 4-diethylamino-4'-nitrostilbene (DEANS) doped polycarbonate (PC) film. The origins of the linear (Pockels) and the quadratic (Kerr) EO effects are discussed. Both the second-order and the third-order susceptibilities corresponding to linear and quadratic EO constants, respectively, were reproduced fairly well by two components, which are due to electronic and molecular orientational contributions. The orientational order of the molecules in the polymer film introduced by the poling was also discussed. Secondly, the quadratic EO effect of a polydiacetylene [PDA3BCMU ] doped in poly(methyl methacrylate) (PMMA) was studied. The change in the extinction coefficient of PDA3BCMU doped in PMMA (3BCMU/PMMA) can be explained in terms of the Stark shift of the transition of the 11111 exciton, and by the conformational change associated with mechanical stress. Thirdly, the transmittance changes of several non-doped polymers, PMMA, poly(vinyl alcohol) (PVA), poly(vinyl acetate) (PVAc), polystyrene (PSt), and poly-N-vinylcarbazole (PVCz) were measured. In the case of PSt, the change in transmittance was concluded to be due mainly to change in the FP cavity length induced by mechanical stress. In other cases, the estimation could not be completed, because of lack of information on the mechanical properties. An experiment to separate changes in the refractive index and film thickness has been devised.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

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