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arXiv · 2309.11438

Brain-inspired computing with fluidic iontronic nanochannels

T. M. Kamsma·J. Kim·K. Kim·W. Q. Boon·C. Spitoni·J. Park·R. van Roij
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Abstract

The brain's remarkable and efficient information processing capability is driving research into brain-inspired (neuromorphic) computing paradigms. Artificial aqueous ion channels are emerging as an exciting platform for neuromorphic computing, representing a departure from conventional solid-state devices by directly mimicking the brain's fluidic ion transport. Supported by a quantitative theoretical model, we present easy to fabricate tapered microchannels that embed a conducting network of fluidic nanochannels between a colloidal structure. Due to transient salt concentration polarisation our devices are volatile memristors (memory resistors) that are remarkably stable. The voltage-driven net salt flux and accumulation, that underpin the concentration polarisation, surprisingly combine into a diffusionlike quadratic dependence of the memory retention time on the channel length, allowing channel design for a specific timescale. We implement our device as a synaptic element for neuromorphic reservoir computing. Individual channels distinguish various time series, that together represent (handwritten) numbers, for subsequent in-silico classification with a simple readout function. Our results represent a significant step towards realising the promise of fluidic ion channels as a platform to emulate the rich aqueous dynamics of the brain.

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T. M. Kamsma, J. Kim, K. Kim, W. Q. Boon, C. Spitoni, J. Park, R. van Roij. 2023-09-20. Brain-inspired computing with fluidic iontronic nanochannels. https://doi.org/10.1073/pnas.2320242121

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