Electro-refraction and electro-absorption in poled polymer Fabry–Perot étalons

Abstract

We present a simple experimental procedure that uses a slowly rotating étalon to measure simultaneously the electro‐refraction and electro‐absorption in a poled polymer. Both effects generally contribute to the measured signal from such material systems and can be distinguished by rotating the sample and observing asymmetric peaks in the signal. The experimental results show the expected increase in both electro‐refraction and electro‐absorption as the probe wavelength approaches the absorption band of the chromophore. Furthermore, the dispersion of the complex electro‐optic coefficient displays a periodic variation that we attribute to multiple‐étalon interference. The stratified nature of the thin‐film structure causes the multiple‐reflection interference. This artifact will pollute most of the standard electro‐optic characterization techniques for poled‐polymer films.