@article{schrickx_gyurek_moore_hernandez-pagan_doherty_kudenov_brendan t. o'connor_2024, title={Flexible Self-Powered Organic Photodetector with High Detectivity for Continuous On-Plant Sensing}, volume={2}, ISSN={["2195-1071"]}, DOI={10.1002/adom.202400005}, abstractNote={AbstractOrganic photodetectors (OPDs) exhibit performance on par with inorganic detectors (e.g., Si) but can be ultrathin, ultra‐lightweight, flexible, and mechanically resilient, opening up opportunities for novel applications including optical sensors for continuous human and plant health monitoring. Here, a high‐performance flexible self‐powered OPD designed for on‐plant optical sensing is developed. The OPD employs an electrode consisting of Ag nanowires (NWs) embedded in a UV‐curable resin to achieve a flexible and thin form factor. In addition, the OPD active layer consisting of D18‐Cl and Y6 is sequentially cast to reduce dark current. The flexible OPD is sensitive to 400–950 nm wavelengths and exhibits photodetector characteristics comparable to state‐of‐the‐art rigid OPDs. The responsivity reaches values of 0.47 A W−1 and specific detectivity exceeds 1012 Jones. Owing to the embedded Ag NW electrodes in a thin substrate (t = 20 µm) and sequentially cast active layers, the detector demonstrates excellent bending stability. The photocurrent remains steady across 4000 cycles with a bending radius of 2 mm. The flexible OPD is demonstrated to effectively detect plant uptake of the rare‐earth metal terbium and sense time‐dependent chlorophyll fluorescence. Thus, this work highlights the potential for OPDs as on‐plant sensors to advance precision agriculture.}, journal={ADVANCED OPTICAL MATERIALS}, author={Schrickx, Harry M. and Gyurek, Sydney and Moore, Caleb and Hernandez-Pagan, Edmaritz and Doherty, Colleen J. and Kudenov, Michael W. and Brendan T. O'Connor}, year={2024}, month={Feb} } @article{altaqui_schrickx_gyurek_sen_escuti_brendan t. o'connor_kudenov_2022, title={Cephalopod-inspired snapshot multispectral sensor based on geometric phase lens and stacked organic photodetectors}, volume={61}, ISSN={["1560-2303"]}, DOI={10.1117/1.OE.61.7.077104}, abstractNote={Abstract. Multispectral imaging (MSI) is a valuable sensing modality for applications that require detecting a scene’s chemical characteristics. Existing MSI techniques utilize a filter wheel or color filter arrays, which are subject to reduced temporal or spatial resolution. In this work, we present a cephalopod-inspired multispectral organic sensor (CiMOS) based on geometric phase lenses (GPLs) and organic photovoltaics (OPVs) to enable aberration-based color sensing. We mimic the approach by which animals with single-type photoreceptors perceive colors via chromatic aberration. The intrinsic chromatic aberration of GPLs allows for multispectral sensing by stacking precisely patterned OPVs within specific spectrally dependent focal lengths. We provide simulations and a proof of concept of the CiMOS and highlight its advantages, including its simple design and snapshot multi-color detection using only a single axial position. Experimental results demonstrate the sensor’s ability to detect four colors with full width at half maximum spectral resolution as low as 35 nm.}, number={7}, journal={OPTICAL ENGINEERING}, author={Altaqui, Ali and Schrickx, Harry and Gyurek, Sydney and Sen, Pratik and Escuti, Michael and Brendan T. O'Connor and Kudenov, Michael}, year={2022}, month={Jul} }