A Transient Photoelectric Spiking Neuron Based on a Highly Robust MgO Composite Threshold Switching Memristor for Selective UV Perception

Abstract

The biological photoreceptors in the retina convert light information into spikes, inspiring the emergence of artificial photoelectric spiking neurons. However, due to the lack of biocompatible and biodegradable characteristics, artificial photoelectric spiking neurons based on threshold switching (TS) devices are not available for bio‐integrated optical medical diagnostics and neuromorphic computing. Here, an artificial photoelectric spiking neuron integrated with a physically transient memristor and photodetector for UV perception is proposed. The transient memristor with a MgO:Mg resistive layer implemented by the co‐sputtering process of MgO and Mg targets shows highly robust TS performance, while the ZnO‐based transient photodetector can selectively detect UV light at power densities below 10 mW cm−2. More interestingly, the frequency of the firing spikes generated by artificial photoelectric spiking neuron increases with the enhancement of UV light intensity. In addition, the recognition accuracy of UV information extracted from the surrounding environment reaches ≈99.8% by spiking neural network consisting of photoelectric spiking neuron when the object that blended into the background are not easily detected. This work demonstrates that the functions of the biological photoreceptors may be truly mimicked by artificial photoelectric spiking neuron with transiency, expanding its application in optical disease diagnosis and implantable visual neuromorphic computing.