(Invited) Silicon Nanocrystals for Optoelectronic Synaptic Devices

Abstract

Nowadays neuromorphic computing is regarded as one of the most promising solutions to the Von Neumann bottleneck due to its high intelligence and low energy consumption. The development of neuromorphic computing critically depends on synaptic devices, which simulate biological synapses in neural systems. The incorporation of light into synaptic devices has been recently inspired by the exciting development of optogenetics in neuroscience. Although optically stimulated synaptic devices with electrical output have been realized, the use of light as the output of synaptic devices under electrical stimulation has not been demonstrated. This may impede the full optoelectronic integration of artificial neural systems for neuromorphic computing. In this talk I shall introduce our recent work on using light-emitting silicon nanocrystals (Si NCs) [1] to fabricate electroluminescent synaptic devices [2,3]. These devices exhibit a series of important synaptic functionalities, including paired-pulse facilitation (PPF), transition from short-term plasticity (STP) to long-term plasticity (LTP) and spike-timing-dependent plasticity (STDP). In the meantime, logic functions such as "AND", "OR", "NAND" and "NOR" can also be realized by using these electroluminescent synaptic devices. References Y. Ni, S. Zhou, S. Y. Zhao, W. B. Peng, D. Yang and X. D. Pi, Silicon nanocrystals: unfading silicon materials for optoelectronics, Materials Science & Engineering R 138, 85-117 (2019). Y. Zhao, Y. Wang, W. Huang, H. Jin, P. W. Huang, H. Wang, K. Wang, D. S. Li, M. S. Xu, D. Yang and X. D. Pi, Developing near-infrared quantum-dot light-emitting diodes to mimic synaptic plasticity, Science China Materials 62, 1470–1478 (2019). Y. Zhao, Z. Y. Ni, H. Tan, Y. Wang, H. Jin, T. X. Nie, M. S. Xu, X. D. Pi and D. Yang, Electroluminescent synaptic devices with logic functions, Nano Energy 54, 383-389 (2018).