Asymmetry-induced resistive switching in Ag-Ag$_{2}$S-Ag memristors enabling a simplified atomic-scale memory design

TL;DR

This paper demonstrates that asymmetry in electrode geometry, rather than electrode material sequence, governs resistive switching in Ag-Ag2S-Ag memristors, enabling simplified atomic-scale memory device design.

Contribution

It reveals that geometrical asymmetry causes resistive switching in Ag2S memristors, challenging traditional electrode sequence models and enabling simpler device fabrication.

Findings

Switching polarity depends on electrode surface asymmetry.

Stable resistive switching observed at room temperature.

Simplified fabrication of atomic-scale memory cells demonstrated.

Abstract

Prevailing models of resistive switching arising from electrochemical formation of conducting filaments across solid state ionic conductors commonly attribute the observed polarity of the voltage-biased switching to the sequence of the active and inert electrodes confining the resistive switching memory cell. Here we demonstrate equivalent, stable switching behavior in metallic Ag-Ag$_{2}$S-Ag nanojunctions at room temperature. Our experimental results and numerical simulations reveal that the polarity of the switchings is solely determined by the geometrical asymmetry of the electrode surfaces. By the lithographical design of a proof of principle device we demonstrate the merits of simplified fabrication of atomic-scale, robust planar Ag$_{2}$S memory cells.