Abstract
Various applications—including brain-like computing and on-chip artificial vision—increasingly demand a combination of electronic and photonic techniques. However, integrating both approaches on a single chip is challenging, and solutions typically rely on disparate components with power-hungry signal conversions. Here we report electro-optical Mott neurons that combine visible light emission with electrical threshold switching, as well as neuron-like oscillations. The devices are based on thin films of sputtered niobium dioxide (NbO2), a Mott insulator–metal transition material, operating at room temperature and emitting light that peaks around 810 nm. Operando measurements reveal an electronic origin to the light emission: charge carrier relaxation initiated by high-field transport in the NbO2. Our devices combine electrical and optical functions within a single material, thereby expanding the options available for future artificial intelligence hardware.
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The data that support the plots within this paper and other findings of the study are available from the corresponding authors upon request.
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Acknowledgements
Part of this work was performed at the Stanford Nanofabrication Facility and Stanford Nano Shared Facilities, which are supported by the National Science Foundation (Award No. ECCS-026822). This work was supported as part of the Center for Reconfigurable Electronic Materials Inspired by Nonlinear Neuron Dynamics (reMIND), an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences. The Laboratory Directed R&D programme of Sandia National Laboratories provided internal support to the reMIND Energy Frontier Research Center. M.I., T.D.B., S.O., A.A.T. and S.K. were partially supported by reMIND. C.P. and M.P. were partially supported by the Laboratory Directed R&D programme. M.I. and S.M.B. were partially supported by the Stanford Graduate Fellowship Program. S.R. acknowledges support from the Air Force Office of Scientific Research (Grant No. FA9550-18-1-0250). E.P. acknowledges partial support from the Stanford SystemX Alliance. This paper describes objective technical results and analyses. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the US Department of Energy or the US Government.
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M.I., S.M.B., S.K. and E.P. conceived the idea. M.I. performed all electrical characterization and electro-optical microscopy measurements. S.M.B. fabricated the NbO2 devices and first observed light emission. M.I. and S.M.B. performed all materials characterizations. M.I. and T.D.B. performed the Raman thermometry and emission spectroscopy measurements with advice from A.A.T. and S.K. M.I. and S.O. measured simultaneous electro-optical activity with advice from A.A.T. C.P. wire-bonded NbO2 devices and assisted with Raman thermometry and emission spectroscopy measurements. C.Z. and T.J.P. grew the NbO2 films with advice from S.R. S.M.B. and M.P. performed the electro-thermal simulations. M.I. analysed all the data and wrote the manuscript with help from S.K. and E.P. All authors have given approval to the final version of the manuscript.
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Nature Electronics thanks Kyung Min Kim, Juan Gabriel Ramírez and Wentao Xu for their contribution to the peer review of this work.
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Supplementary Figs. 1–20, discussion and Tables 1 and 2.
Supplementary Video 1
Video capturing light emission in NbO2 devices during electrical threshold switching displayed in Fig. 2b.
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Islam, M., Bohaichuk, S.M., Brown, T.D. et al. An electro-optical Mott neuron based on niobium dioxide. Nat Electron 8, 672–679 (2025). https://doi.org/10.1038/s41928-025-01406-1
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DOI: https://doi.org/10.1038/s41928-025-01406-1
