Multifunctional Two-Terminal Optoelectronic Synapse Based on Zinc Oxide/Poly(3-hexylthiophene) Heterojunction for Neuromorphic Computing

With the advantages of wide bandwidth, low power consumption, high propagation speed, and excellent interconnectivity, the light-tunable synapse is regarded as one of the most promising candidates to pave the way for constructing neuromorphic computing and overcoming the von Neumann bottleneck. Herein, an optoelectronic synaptic memristor based on zinc oxide/poly(3-hexylthiophene) (ZnO/P3HT) heterojunction is fabricated via a simple two-step spin coating process. The prepared device can simulate typical neuromorphic manners, such as excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), the transformation from short-term plasticity (STP) to long-term plasticity (LTP), and "learning-experience" behavior by modulating the applied light pulses. In addition to the optoelectronic synaptic behaviors, our device incorporates light logic functions ("AND" and "OR" operations) and optical information detection and memory functions analogous to those in the human's visual recognition memory system.