Synaptic-Like Plasticity in 2D Nanofluidic Memristor from Competitive Bicationic Transport

TL;DR

This study demonstrates synaptic-like plasticity in a 2D nanofluidic memristor using molecular dynamics, showing dynamic ionic permeability changes with ultra-low energy dissipation, mimicking biological synapses.

Contribution

It introduces a novel 2D nanofluidic memristor exhibiting repeatable synaptic-like plasticity driven by competitive bicationic transport, with detailed molecular insights.

Findings

Demonstrates synaptic-like plasticity in a 2D membrane.

Achieves ultra-low energy dissipation of 0.1--100 aJ per spike.

Reveals molecular mechanisms underlying ionic transport and plasticity.

Abstract

Synaptic plasticity, the dynamic tuning of signal transmission strength between neurons, serves as a fundamental basis for memory and learning in biological organisms. This adaptive nature of synapses is considered one of the key features contributing to the superior energy efficiency of the brain. In this study, we utilize molecular dynamics simulations to demonstrate synaptic-like plasticity in a subnanoporous 2D membrane. We show that a train of voltage spikes dynamically modifies the membrane's ionic permeability in a process involving competitive bicationic transport. This process is shown to be repeatable after a given resting period. Due to a combination of sub-nm pore size and the atomic thinness of the membrane, this system exhibits energy dissipation of 0.1--100 aJ per voltage spike, which is several orders of magnitude lower than 0.1--10 fJ per spike in the human synapse. We reveal the underlying physical mechanisms at molecular detail and investigate the local energetics underlying this apparent synaptic-like behavior.