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1. Machine Learning Based Prediction of Erbium-Doped Fiber WDM Line Amplifier Gain Spectra

   Zhu, Shengxiang; Gutterman, Crag L.; Mo, Weiyang; Li, Yao; Zussman, Gil; Kilper, Daniel C. (January 2018, 2018 European Conference on Optical Communication)

   Machine learning based modelling of Erbium-Doped Fiber Amplifiers (EDFA) is used to determine wavelength dependent gain for use in optical transmission systems, and achieves root mean square error (RMSE) of 0.08, 0.18, and 0.27 dB under input ranges of +/- 3, 6, 9 dB. 

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2. An LPTV Noise Cancellation Technique for a 0.9-V Filtering-by-Aliasing Receiver Front-End with >67-dB Stopband Rejection

   https://doi.org/10.1109/CICC.2019.8780315  

   Bu, Shi; Hameed, Sameed; Pamarti, Sudhakar (April 2019, 2019 IEEE Custom Integrated Circuits Conference)

   A linear periodically time-varying (LPTV) noise cancellation technique for filtering-by-aliasing (FA) receivers is presented in this paper. Fabricated in a 28-nm CMOS process, it improves the noise Figure (NF) by about 3 dB while achieving over 67-dB stopband rejection with a transition bandwidth of only four times the RF BW. A minimum in-band NF of 3.2 dB is demonstrated. With an upfront -path filter to further enhance the linearity, the measured out-of-band IIP 3 is + 18 dBm and the blocker 1-dB compression point is + 9 dBm. Operating under a 0.9V supply, it consumes 61-mW power at 500-MHz LO. 

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3. Reaction amplification with a gain: Triplet exciton–mediated quantum chain using mixed crystals with a tailor-made triplet sensitizer

   https://doi.org/10.1073/pnas.2401982121  

   Paul, Indrajit; Konieczny, Krzysztof A.; Chavez, Roberto; Garcia-Garibay, Miguel A. (April 2024, Proceedings of the National Academy of Sciences)

   Photochemical valence bond isomerization of a crystalline Dewar benzene diacid monoanion salt with an acetophenone-linked piperazinium cation that serves as an intramolecular triplet energy sensitizer (DB-AcPh-Pz) exhibits a quantum chain reaction with as many as 450 product molecules per photon absorbed (F ≈ 450). By contrast, isomorphous crystals of the Dewar benzene diacid monosalt of an ethylbenzene-linked piperazinium (DB-EtPh-Pz) lacking a triplet sensitizer showed a less impressive quantum yield of ca. F ≈ 22. To establish the critical importance of a triplet excited state carrier in the adiabatic photochemical reaction we prepared mixed crystals with DB-AcPh-Pz as a dilute triplet sensitizer guest in crystals of DB-EtPh-Pz. As expected from the their high structural similarities, solid solutions were easily formed with the triplet sensitizer salt in the range of 0.1% to 10%. Experiments carried out under conditions where light is absorbed by the triplet sensitizer-linked DB-AcPh-Pz can be used to initiate a triplet state adiabatic reaction from 3DB-AcPh-Pz to 3HB*-AcPh-Pz, which can serve as a chain carrier and transfer energy to an unreacted DB-EtPh-Pz where exciton delocalization in the crystalline solid solution can help carry out an efficient energy transfer and enable a quantum chain employing the photoproduct as a triplet chain carrier. Excitation of mixed crystals with a little as 0.1% triplet sensitizer resulted in an extraordinarily high quantum yield F ≈ 517. 

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4. Dual‐Functional High‐Entropy Polymer Exhibiting Giant Cross‐Energy Couplings at Low Fields

   https://doi.org/10.1002/smsc.202400624  

   Rui, Guanchun; Zhu, Wenyi; Li, Li; Lee, Jongcheol; Guo, Yiwen; Zou, Qin; Wu, Siyu; Li, Ruipeng; Lannuzel, Thierry; Domingues_Dos_Santos, Fabrice; et al (June 2025, Small Science)

   A key component of cooling devices is the transfer of entropy from the cold load to heat sink. An electrocaloric (EC) polymer capable of generating both large electrocaloric effect (ECE) and substantial electroactuation can enable EC cooling devices to pump heat without external mechanisms, resulting in compact designs and enhanced efficiency. However, achieving both high ECE and significant electroactuation remains challenging. Herein, it is demonstrated that poly(vinylidene fluoride‐trifluoroethylene‐chlorofluoroethylene‐double bond) [P(VDF‐TrFE‐CFE‐DB)] tetrapolymers can simultaneously generate high electrocaloric effects and electroactuations under low fields. These P(VDF‐TrFE‐CFE‐DB) tetrapolymers are synthesized through the dehydrochlorination of P(VDF‐TrFE‐CFE) terpolymer. By facile tuning the composition of the initial terpolymer to avoid pure relaxor state, tetrapolymers with optimal DB compositions are achieved, near the critical endpoint of normal ferroelectric phase with diffused phase transition. The nearly vanishing energy barriers between the nonpolar to polar phases result in a strong electrocaloric response and significant electroactuation. Specifically, the P(VDF‐TrFE‐CFE‐DB) tetrapolymer exhibits an EC entropy change ΔSof 100 J kg⁻¹ K⁻¹under 100 MV m⁻¹: comparable to state‐of‐the‐art (SOA) EC polymers, while delivering nearly twice the electroactuation of the SOA EC polymers. This work presents a general strategy for developing EC materials that combine large electrocaloric effect and electroactuation at low electric fields. 

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5. Multi-Span OSNR and GSNR Prediction using Cascaded Learning

   https://doi.org/10.1364/OFC.2025.Tu3I.6  

   Wang, Zehao; Borraccini, Giacomo; D’Amico, Andrea; Huang, Yue-Kai; Wang, Ting; Kilper, Dan; Asahi, Koji; Chen, Tingjun (March 2025, Optica Publishing Group)

   We implement a cascaded learning framework leveraging three different EDFA and fiber component models for OSNR and GSNR prediction, achieving MAEs of 0.20 and 0.14 dB over a 5-span network under dynamic channel loading. 

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