Nanowire photodetectors: path to single physical artificial neurons

Neurons are basic units for information processing in biological systems. Inspired by the information-processing efficiency of biological systems, artificial neural networks (ANNs) have been studied for decades. However, it remains challenging today to realize single physical artificial neurons so that an ANN can be constructed in a bottom-up manner. Herein, we show that by using an innovative light-detecting semiconductor nanowire structure, neuronal features much closer to single, physical artificial neurons can be emulated, including excitation and inhibition, threshold, refractory period, and temporal summation. The analogy between the presented neuron-like nanowire photodetectors and neurons in the human retina system is also discussed. This study lays the cornerstone for the bottom-up construction of a physical ANN.