Deep-ultraviolet-triggered neuromorphic functions in In-Zn-O phototransistors

In recent years, photoelectronic synaptic devices have emerged as a platform for use in next-generation neuromorphic systems and artificial neural networks (ANNs). In this paper, we report an artificial photoelectronic synapse based on an ion-gel gated In-Zn-O phototransistor. The phototransistor is stimulated by a deep ultraviolet light spike, and it can process and store information in the form of an electric current. Key biological synaptic behaviors were investigated, including excitatory post-synaptic current and paired pulse facilitation. Furthermore, channel conduction can be changed by photoelectric synergy in order to simulate potentiation and depression behavior in the human brain. Most importantly, four forms of spike-timing dependent plasticity learning principles were realized by a photoelectric hybrid stimulation. Our studies provide a path towards hybrid photoelectronic ANNs capable of performing solar-blind sensitive tasks.