Sodium-Controlled Interfacial Resistive Switching in Thin Film Niobium Oxide for Neuromorphic Applications

A double layer 2-terminal device is employed to show Na-controlled interfacial resistive switching and neuromorphic behavior. The bilayer is based on interfacing biocompatible NaNbO₃ and Nb₂O₅, which allows the reversible uptake of Na⁺ in the Nb₂O₅ layer. We demonstrate voltage-controlled interfacial barrier tuning via Na⁺ transfer, enabling conductivity modulation and spike-amplitude- and spike-timing-dependent plasticity. The neuromorphic behavior controlled by Na⁺ ion dynamics in biocompatible materials shows potential for future low-power sensing electronics and smart wearables with local processing.