Liu Xin, Wang Danhao, Chen Wei, Kang Yang, Fang Shi, Luo Yuanmin, Luo Dongyang, Yu Huabin, Zhang Haochen, Liang Kun, Fu Lan, Ooi Boon S, Liu Sheng, Sun Haiding
iGaN Laboratory, School of Microelectronics, University of Science and Technology of China, Hefei, Anhui, China.
Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra, ACT, Australia.
Nat Commun. 2024 Sep 3;15(1):7671. doi: 10.1038/s41467-024-51194-z.
Optoelectronic synapses, leveraging the integration of classic photo-electric effect with synaptic plasticity, are emerging as building blocks for artificial vision and photonic neuromorphic computing. However, the fundamental working principles of most optoelectronic synapses mainly rely on physical behaviors while missing chemical-electric synaptic processes critical for mimicking biorealistic neuromorphic functionality. Herein, we report a photoelectrochemical synaptic device based on p-AlGaN/n-GaN semiconductor nanowires to incorporate chemical-electric synaptic behaviors into optoelectronic synapses, demonstrating unparalleled dual-modal plasticity and chemically-regulated neuromorphic functions through the interplay of internal photo-electric and external electrolyte-mediated chemical-electric processes. Electrical modulation by implementing closed or open-circuit enables switching of optoelectronic synaptic operation between short-term and long-term plasticity. Furthermore, inspired by transmembrane receptors that connect extracellular and intracellular events, synaptic responses can also be effectively amplified by applying chemical modifications to nanowire surfaces, which tune external and internal charge behaviors. Notably, under varied external electrolyte environments (ion/molecule species and concentrations), our device successfully mimics chemically-regulated synaptic activities and emulates intricate oxidative stress-induced biological phenomena. Essentially, we demonstrate that through the nanowire photoelectrochemical synapse configuration, optoelectronic synapses can be incorporated with chemical-electric behaviors to bridge the gap between classic optoelectronic synapses and biological synapses, providing a promising platform for multifunctional neuromorphic applications.
光电突触利用经典光电效应与突触可塑性的整合，正逐渐成为人工视觉和光子神经形态计算的构建模块。然而，大多数光电突触的基本工作原理主要依赖于物理行为，而缺少对模拟生物逼真神经形态功能至关重要的化学 - 电突触过程。在此，我们报道了一种基于p - AlGaN/n - GaN半导体纳米线的光电化学突触器件，将化学 - 电突触行为整合到光电突触中，通过内部光电和外部电解质介导的化学 - 电过程的相互作用，展示了无与伦比的双模态可塑性和化学调节的神经形态功能。通过实现闭路或开路进行电调制，能够在短期和长期可塑性之间切换光电突触操作。此外，受连接细胞外和细胞内事件的跨膜受体的启发，通过对纳米线表面进行化学修饰来调节外部和内部电荷行为，也可以有效地放大突触反应。值得注意的是，在不同的外部电解质环境（离子/分子种类和浓度）下，我们的器件成功模拟了化学调节的突触活动，并模拟了复杂的氧化应激诱导的生物现象。本质上，我们证明了通过纳米线光电化学突触配置，光电突触可以与化学 - 电行为相结合，弥合经典光电突触与生物突触之间的差距，为多功能神经形态应用提供了一个有前景的平台。
