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A neuromorphic imager based on a cascaded optoelectronic synapse

Nature Electronics (2026)Cite this article

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Abstract

The human retina can provide inspiration for the development of optoelectronic devices for artificial vision systems. It has, in particular, a curved geometry for low optical aberration imaging and is capable of signal preprocessing, in part due to its high synaptic facilitation. However, it remains challenging to create artificial synaptic devices with mechanical softness, curvilinear form factors and superior synaptic facilitation. Here we report a cascaded two-stage optoelectronic synapse that uses silicon photovoltaic cells to modulate sodium-alginate-gated synaptic transistors. The photovoltaic cells and an electric double-layer capacitor convert the initial light signal into a gate voltage (stage one), which then controls the postsynaptic current in the channel of the synaptic transistor (stage two). This cascaded synaptic signal transmission mechanism results in high synaptic facilitation of the postsynaptic signal. The system exhibits stable and long-term linearly potentiated characteristics, enhancing the accuracy of pattern recognition. We use an array of the cascaded optoelectronic synapses to create a curvy, kirigami-structured neuromorphic imager, which mimics the curved geometry and neural signal transmission of the human retina and provides visual information sensing and preprocessing functions.

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Fig. 1: Overview and working principle of the cascaded optoelectronic synapse.
Fig. 2: Device structure and electrical characteristics of the EDL synaptic transistor.
Fig. 3: Cascaded optoelectronic synapse.
Fig. 4: Linearly potentiated synaptic plasticity for neuromorphic computing.
Fig. 5: Curvy neuromorphic imager.

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Data availability

The data that support the findings of this study or additional data related to this paper are available from the authors upon request.

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Acknowledgements

C.Y. gives thanks for the financial support from the National Science Foundation (CAREER Grant No. 2224645, ECCS Grant No. 1509763 and CPS Grant No. 2227062) and the Office of Naval Research Young Investigator Program (Grant No. N00014-18-1-2338).

Author information

Author notes

  1. These authors contributed equally: Yuntao Lu, Zhoulyu Rao, Hyunseok Shim.

Authors and Affiliations

  1. Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA, USA

    Yuntao Lu, Zhoulyu Rao & Hyunseok Shim

  2. Materials Research Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Zhoulyu Rao & Cunjiang Yu

  3. School of Electrical and Electronics Engineering, Pusan National University, Busan, Republic of Korea

    Hyunseok Shim

  4. School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea

    Young Min Song

  5. Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong, China

    Zhiyong Fan

  6. Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong, China

    Zhiyong Fan

  7. Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, China

    Chuanfei Guo

  8. Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA

    Cunjiang Yu

  9. Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, USA

    Cunjiang Yu

  10. Materials Research Institute, Pennsylvania State University, University Park, PA, USA

    Cunjiang Yu

  11. Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

  12. Department of Materials Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

  13. Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

  14. Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

  15. Nick Holonyak Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

  16. Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA

    Cunjiang Yu

Authors
  1. Yuntao Lu
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  2. Zhoulyu Rao
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  3. Hyunseok Shim
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  4. Young Min Song
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  5. Zhiyong Fan
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  6. Chuanfei Guo
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Contributions

Y.L. and C.Y. conceived the study and designed the research. Y.L., Z.R. and H.S. performed the experiments. Y.L., H.S., Y.M.S., Z.F., C.G. and C.Y. analysed the data. Y.L. and H.S. performed the simulation. Y.L., Z.R., H.S. and C.Y. wrote the paper. All the authors revised the paper.

Corresponding author

Correspondence to Cunjiang Yu.

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Nature Electronics thanks Huipeng Chen, Changsoon Choi and Nazek El-Atab for their contribution to the peer review of this work.

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Supplementary Information

Supplementary Note, Table 1 and Figs. 1–21.

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Lu, Y., Rao, Z., Shim, H. et al. A neuromorphic imager based on a cascaded optoelectronic synapse. Nat Electron (2026). https://doi.org/10.1038/s41928-025-01540-w

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