Two-dimensional Clay Channels for Tunable Nanofluidic Memristor

TL;DR

This paper presents a scalable, reconfigurable nanofluidic memristor based on vermiculite channels that exhibits tunable memory effects, neuromorphic functionalities, and potential for bio-inspired computing.

Contribution

It introduces a simple, experimentally validated method to switch memory states in ionic devices by electrode configuration, without altering the device structure or chemistry.

Findings

Achieved polarity-dependent memory switching between distinct loops.

Demonstrated memristive behavior in both in-plane and out-of-plane configurations.

Fabricated devices with channel lengths from centimeters to nanometers, showing scalability.

Abstract

Dynamic reconfiguration of charge carriers in confined ion-channels under electrical stimulation produces memory effects, where the internal resistance depends on history of the electric field. Vermiculite nanofluidic devices harness this effect to store and process information within a single component. We report switching between distinct memory loops by tuning ion transport pathways, governed by asymmetrical device architecture and intrinsic surface-charge. Polarity-dependent memory switching between crossing-1 and crossing-2 loops is achieved solely by altering electrode configurations, without modifying electrolyte, channel surface chemistry or device structure: providing mechanistic insights into ionic memristors through a straightforward, experimentally validated strategy. The memristive characteristics are demonstrated in both in-plane and out-of-plane channel configurations with channel lengths spanning from centimeters to micrometers length scales using re-stacked vermiculite membranes and further investigated for miniaturization with devices having nanometer scale channel lengths, fabricated via ultramicrotomy method. Furthermore, we demonstrate neuromorphic functionalities, including synaptic potentiation-depression and programmable memory retention, highlighting potential for bio-inspired computing systems. Cost-effective and scalable fabrication solution processed vermiculite membrane memristors pave the way for practical integration of nanofluidic memristors for neuromorphic computing applications.