Emulation of auditory senses depending on chaotic dynamics of threshold switching memristor

Abstract

Emulating the auditory sense is a significant challenge in terms of both integration and energy consumption for handling complicated spatiotemporal information. Here, we demonstrate how to utilize the chaotic dynamics of a threshold switching memristor, which usually acts as a leaky integrate and fire neuron in the neuromorphic network, to encode the frequency and amplitude in auditory information. We fabricate a Pd/Nb/NbOx/Nb/Pd memristor dominated by the Poole–Frankel conduction mechanism, set its state at the edge of chaos, and stimulate it using periodic perturbations. The memristor's responses to the perturbation frequencies can be categorized into three zones. Two are phase locking with linear phase–frequency relationships, and one has a hyperbolic spike number–frequency relationship. The memristor system also enables intensity coding and tonotopy by modulating the response spikes in either the locked phase or spike number. Based on the emulation of these two features, the memristor system demonstrates sound location and frequency mixing. Our study suggests a novel routine for handling the auditory and visual senses using threshold-switching memristor arrays to enhance the efficiency of neuromorphic networks. (Figure presented.).