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  1. Organic electro-optic (EO) materials incorporated into silicon-organic hybrid and plasmonic-organic hybrid devices have enabled new records in EO modulation performance. We report a new series of nonlinear optical chromophores engineered by theory-guided design, utilizing bis(4-dialkylaminophenyl)heteroarylamino donor moieties to greatly enhance molecular hyperpolarizabilities. Hyperpolarizabilities predicted using density functional theory were validated by hyper-Rayleigh scattering measurements, showing strong prediction/experiment agreement and >2-fold advancement in static hyperpolarizability over the best prior chromophores. Electric field poled thin films of these chromophores showed significantly enhanced EO coefficients ( r 33 ) and poling efficiencies ( r 33 / E p ) at low chromophore concentrations compared with state-of-the-art chromophores such as JRD1 . The highest performing blend, containing just 10 wt% of the novel chromophore BTP7 , showed a 12-fold enhancement in poling efficiency per unit concentration vs. JRD1 . Our results suggest that further improvement in chromophore hyperpolarizability is feasible without unacceptable tradeoffs with optical loss or stability. 
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  2. Abstract

    High performance organic electro‐optic (OEO) materials enable ultrahigh bandwidth, small footprint, and extremely low drive voltage in silicon‐organic hybrid and plasmonic‐organic hybrid photonic devices. However, practical OEO materials under device‐relevant conditions are generally limited to performance of300 pm V−1(10× the EO response of lithium niobate). By means of theory‐guided design, a new series of OEO chromophores is demonstrated, based on strong bis(4‐dialkylaminophenyl)phenylamino electron donating groups, capable of EO coefficients (r33) in excess of 1000 pm V−1. Density functional theory modeling and hyper‐Rayleigh scattering measurements are performed and confirm the large improvement in hyperpolarizability due to the stronger donor. The EO performance of the exemplar chromophore in the series, BAY1, is evaluated neat and at various concentrations in polymer host and shows a nearly linear increase inr33and poling efficiency (r33/Ep, Epis poling field) with increasing chromophore concentration. 25 wt% BAY1/polymer composite shows a higher poling efficiency (3.9 ±0.1 nm2V−2) than state‐of‐the‐art neat chromophores. Using a high‐ε charge blocking layer with BAY1, a record‐highr33(1100 ±100 pm V−1) and poling efficiency (17.8 ±0.8 nm2V−2) at 1310 nm are achieved. This is the first reported OEO material with electro‐optic response larger than thin‐film barium titanate.

     
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