Author(s): He, XY (He, Xiaoying); Xu, MH (Xu, Minghao); Liu, SL (Liu, Shilin); Wang, K (Wang, Kun); Cao, BW (Cao, Bowen); Rao, L (Rao, Lan); Xin, XJ (Xin, Xiangjun)

Source: PHOTONICS RESEARCH Volume: 12  Issue: 6  Pages: 1167-1174  

DOI: 10.1364/PRJ.516207  Published Date: 2024 JUN 1  

Abstract: By combining the good charge transport property of graphene and the excellent photo-carrier generation characteristic of perovskite nanocrystal, we propose and demonstrate an ionic-gated synaptic transistor based on CsPbBr3/graphene heterojunction for bipolar photoresponse. Controlling the potential barrier of the CsPbBr3/graphene heterojunction by the ionic-gate of the electrical double-layer effect can promote the separation of photogenerated carriers and effectively retard their recombination. Using the ionic-gate-tunable Fermi level of graphene and the pinning effect of perovskite nanocrystal, the bipolar photocurrent responses corresponding to the excitatory and inhibitory short-term and long-term plasticity are realized by adjusting the negative gate bias. A series of synaptic functions including logic operation, Morse coding, the optical memory and electrical erasure effect, and light-assisted re-learning have also been demonstrated in an optoelectronic collaborative pathway. Furthermore, the excellent optical synaptic behaviors also contribute to the handwritten font recognition accuracy of similar to 95% in artificial neural network simulations. The results pave the way for the fabrication of bipolar photoelectric synaptic transistors and bolster new directions in the development of future integrated human retinotopic vision neuromorphic systems. (c) 2024 Chinese Laser Press