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Unsupervised character recognition with graphene memristive synapses

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Abstract

Memristive devices being applied in neuromorphic computing are envisioned to significantly improve the power consumption and speed of future computing platforms. The materials used to fabricate such devices will play a significant role in their viability. Graphene is a promising material, with superb electrical properties and the ability to be produced in large volumes. In this paper, we demonstrate that a graphene-based memristive device could potentially be used as synapses within spiking neural networks (SNNs) to realise spike timing-dependant plasticity for unsupervised learning in an efficient manner. Specifically, we verify the operation of two SNN architectures tasked for single-digit (0–9) classification: (i) a single layer network, where inputs are presented in \(5\times 5\) pixel resolution, and (ii) a larger network capable of classifying the dataset. Our work presents the first investigation and large-scale simulation of the use of graphene memristive devices to perform a complex pattern classification task. In favour of reproducible research, we will make our code and data publicly available. This can pave the way for future research in using graphene devices with memristive capabilities in neuromorphic computing architectures.

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Availability of data and materials

The data and materials will be made publicly available.

Code availability

Our code is made available at: https://github.com/jc427648/SNN-GrapheneSynapses.git.

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Acknowledgements

Ben Walters acknowledges the Domestic Research Training Program Scholarship (DRTPS) (Australia). Corey Lammie acknowledges the Domestic Prestige Research Training Program Scholarship (DPRTPS) (Australia), IBM PhD Fellowship (IBM, US), and the Circuits and Systems (CAS) Society Predoctoral Grant (IEEE, US).

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Authors and Affiliations

  1. College of Science and Engineering, James Cook University, 1 James Cook Drive, Townsville, QLD, 4811, Australia

    Ben Walters, Corey Lammie, Mohan V Jacob & Mostafa Rahimi Azghadi

  2. School of Electrical and Information Engineering, Tian** University, Tian**, China

    Shuangming Yang

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Walters, B., Lammie, C., Yang, S. et al. Unsupervised character recognition with graphene memristive synapses. Neural Comput & Applic 36, 1569–1584 (2024). https://doi.org/10.1007/s00521-023-09135-2

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