Characterization of electro-optic polymer films by use of decal-deposited reflection Fabry Perot microcavities

Abstract

We have used resonant reflection mode Fabry–Perot microcavities (RFPM’s) to determine linear optical and electro-optical properties of poled nonlinear optical polymers (NLP’s). Measured reflectances from angular scans of RFPM’s have been analyzed with an electromagnetic plane-wave multilayer analysis that took into account the anisotropic nature of the NLP layer. We have numerically investigated the mutual dependence of refractive indices and layer thickness and the accuracy of the results obtained. As an illustration of this characterization technique, the refractive indices of a 10 mol. % Disperse Red 1/poly(methyl methacrylate) side-chain NLP have been determined to within ±0.005, the NLP layer thicknesses to within 1%, and electro-optic coefficients to within 5%. We optimized RFPM structures for measurements at the wavelength λ=430 nm by changing the electrode metal from gold to aluminum. Using a guest–host NLP, 5 wt. % diphenyl-tricyanovinyl-aniline in poly(methyl methacrylate), we show that the method is capable of measuring electrorefraction and electroabsorption as well as a converse piezoelectric contribution. We show that a NLP decal deposition technique is particularly well suited to fabrication of these RFPM’s.