Electrooptic characterization of organic media

The authors have developed an electrooptic characterization apparatus based on an AC-modulated Senarmont compensator. The apparatus is particularly suitable for studying the electrooptic response of thin polymer films. The system is capable of measuring the Pockel´s effect at a variety of wavelengths with a minimum phase shift sensitivity of 1 μrad. Sample-to-sample variations in the coefficient measurements are less than 15%. The authors have made a systematic evaluation of thin, poled electrooptic polymer films on coplanar electrodes to demonstrate the usefulness of the apparatus. Corrections for the fringing effects of the applied electric field are described. The reproducibility of the electrooptic data through an examination of the polymer thickness dependence has been verified. The authors have also measured the poling field dependence of the electrooptic coefficient and obtained a best-fit molecular dipole value in excellent agreement with the reported value obtained from EFISH and solvatochromism measurements