Flexible electro-optical neuromorphic transistors with tunable synaptic plasticity and nociceptive behavior

Abstract An electro-optical modulation synaptic device is proposed; it can emulate both brain-like processing and nervous perception functions by using a special nanoparticle-based conductive channel for the first time. In an electrical-processing synapse (EPS), ion diffusion behaviors during point contact and plane contact showed short-term plasticity with different gains and various synaptic functions such as paired-pulse facilitation, memory enhancement, spatiotemporal signal processing, and fault-tolerant behavior of logic operations. The EPS array is also mechanically flexible; the postsynaptic current retained 41.8% of the initial value after 10,000 bends, which represents the largest number of bending cycles of a flexible synaptic transistor so far. As a nervous optical sensing-processing synapse (OSPS), it can respond to ultraviolet light of different intensities and durations under sensitive millivolt reading voltage and also act as nociceptors to realize the pain perception. The ability of synaptic device to adjust their responses is important to connect brain-like devices to an artificial nervous system, so this electro-optical synaptic unit is a promising candidate for use in neuromorphic and flexible electronics, to combine brain-like processing and artificial sensory nerves.