Non-exponential resistive switching in Ag2S memristors: a key to nanometer-scale non-volatile memory devices

The dynamics of resistive switchings in nanometer-scale metallic junctions formed between an inert metallic tip and an Ag film covered by a thin Ag 2 S layer are investigated. Our thorough experimental analysis and numerical simulations revealed that the resistance change upon a switching bias voltage pulse exhibits a strongly non-exponential behaviour yielding markedly different response times at different bias levels. Our results demonstrate the merits of Ag 2 S nanojunctions as nanometer-scale non-volatile memory cells with stable switching ratios, high endurance as well as fast response to write/erase, and an outstanding stability against read operations at technologically optimal bias and current levels. The non-exponential dynamics of resistive switchings in Ag 2 S memristive nanojunctions provides an ideal basis for non-volatile memory applications.