Abstract
Moiré quantum materials host exotic electronic phenomena through enhanced internal Coulomb interactions in twisted two-dimensional heterostructures1,2,3,4. When combined with the exceptionally high electrostatic control in atomically thin materials5,6,7,8, moiré heterostructures have the potential to enable next-generation electronic devices with unprecedented functionality. However, despite extensive exploration, moiré electronic phenomena have thus far been limited to impractically low cryogenic temperatures9,10,11,12,13,14, thus precluding real-world applications of moiré quantum materials. Here we report the experimental realization and room-temperature operation of a low-power (20 pW) moiré synaptic transistor based on an asymmetric bilayer graphene/hexagonal boron nitride moiré heterostructure. The asymmetric moiré potential gives rise to robust electronic ratchet states, which enable hysteretic, non-volatile injection of charge carriers that control the conductance of the device. The asymmetric gating in dual-gated moiré heterostructures realizes diverse biorealistic neuromorphic functionalities, such as reconfigurable synaptic responses, spatiotemporal-based tempotrons and Bienenstock–Cooper–Munro input-specific adaptation. In this manner, the moiré synaptic transistor enables efficient compute-in-memory designs and edge hardware accelerators for artificial intelligence and machine learning.
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Data availability
Data for all figures are available at the Harvard Dataverse repository (https://doi.org/10.7910/DVN/1LZUH5).
Code availability
Code for all algorithms is available from the Harvard Dataverse repository (https://doi.org/10.7910/DVN/1LZUH5).
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Acknowledgements
This research was primarily supported by the National Science Foundation Materials Research Science and Engineering Center at Northwestern University (Grant DMR-1720139). Work in the P.J.-H. group was partially supported by the National Science Foundation (QII-TAQS Grant OMA-1936263), by the Massachusetts Institute of Technology/Microsystems Technology Laboratories Samsung Semiconductor Research Fund, by the Gordon and Betty Moore Foundation Emergent Phenomena in Quantum Systems Initiative (Grant GBMF9463) and by the Fundación Ramon Areces. P.J.-H. and Q.M. also acknowledge partial support from the Air Force Office of Scientific Research (Grant FA9550-21-1-0319). This work was performed in part at the Harvard University Center for Nanoscale Systems, a member of the National Nanotechnology Coordinated Infrastructure Network, which is supported by the National Science Foundation (Grant ECCS-1541959). Q.M. acknowledges support from the National Science Foundation Convergence Program (Grant ITE-2235945) and the Canadian Institute for Advanced Research Azrieli Global Scholars Program. Z.Z. acknowledges support from the National Science Foundation Graduate Research Fellowship (Grant 2141064). K.W. and T.T. acknowledge support from the Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research (Grants 19H05790, 20H00354 and 21H05233).
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P.J.-H., Q.M. and M.C.H. conceived the idea and experiments. X.Y., Z.Z., X.W. and S.E.L. fabricated devices and performed all measurements and analysis under the supervision of P.J.-H., Q.M. and M.C.H. X.Y., V.K.S. and J.H.Q. performed the neural network simulations. S.-Y.X. contributed to understanding the underlying device mechanism. K.W. and T.T. grew the bulk hexagonal boron nitride single crystals. All authors discussed the results and wrote the manuscript.
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Yan, X., Zheng, Z., Sangwan, V.K. et al. Moiré synaptic transistor with room-temperature neuromorphic functionality. Nature 624, 551–556 (2023). https://doi.org/10.1038/s41586-023-06791-1
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DOI: https://doi.org/10.1038/s41586-023-06791-1
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