CC BY 3.0 UnportedSteglich, PatrickMai, ChristianVillringer, ClausMai, Andreas2021-11-162021-11-162020https://oa.tib.eu/renate/handle/123456789/7312https://doi.org/10.34657/6359We report on the direct observation and simultaneous use of the linear and quadratic electro-optical effect and propose a method by which higher-order susceptibilities of electro-optical materials can be determined. The evaluation is based on the separation of the second- and third-order susceptibilities and the experimental technique uses a slot waveguide ring resonator fabricated in integrated photonic circuit technology, which is embedded by a guest-host polymer system consisting of the azobenzene dye Disperse Red 1 in a poly(methyl methacrylate) matrix as an active electro-optical material. The contribution of both effects on the electro-optical response under the influence of static and time-varying electrical fields is investigated. We show that the quadratic electro-optical effect has a significant influence on the overall electro-optical response even with acentric molecular orientated molecules. Our findings have important implications for developing electro-optical devices based on polymer-filled slot waveguides and give rise to advanced photonic circuits. © 2020 IOP Publishing Ltd.enghttps://creativecommons.org/licenses/by/3.0/530Electro-optical effectsElectro-optical polymersPhotonic devicesPhotonic integrated circuitSilicon photonicsSilicon-organic hybrid technologySlot waveguideArticle