Plasmonic Optoelectronic Memristor Enabling Fully Light‐Modulated Synaptic Plasticity for Neuromorphic Vision

Abstract

Exploration of optoelectronic memristors with the capability to combine sensing and processing functions is required to promote development of efficient neuromorphic vision. In this work, the authors develop a plasmonic optoelectronic memristor that relies on the effects of localized surface plasmon resonance (LSPR) and optical excitation in an Ag–TiO2 nanocomposite film. Fully light‐induced synaptic plasticity (e.g., potentiation and depression) under visible and ultraviolet light stimulations is demonstrated, which enables the functional combination of visual sensing and low‐level image pre‐processing (including contrast enhancement and noise reduction) in a single device. Furthermore, the light‐gated and electrically‐driven synaptic plasticity can be performed in the same device, in which the spike‐timing‐dependent plasticity (STDP) learning functions can be reversibly modulated by visible and ultraviolet light illuminations. Thereby, the high‐level image processing function, i.e., image recognition, can also be performed in this memristor, whose recognition rate and accuracy are obviously enhanced as a result of image pre‐processing and light‐gated STDP enhancement. Experimental analysis shows that the memristive switching mechanism under optical stimulation can be attributed to the oxidation/reduction of Ag nanoparticles due to the effects of LSPR and optical excitation. The authors' work proposes a new type of plasmonic optoelectronic memristor with fully light‐modulated capability that may promote the future development of efficient neuromorphic vision.

Photoelectric Memristor-Based Machine Vision for Artificial Intelligence Applications

“…(d) Comparison of image learning and recognition rates with and without retina-like preprocessing. Reproduced with permission from ref . Copyright 2022 Wiley-VCH.…”

“…The retina on the eyeball first captures image information and converts it into electrical signals for low-level preprocessing on the retina. Then, these signals were transmitted via the optic nerve to the visual cortex, which performs the functions of parallel high-level processing and memory of the acquired image information …”

“…(c) Schematic diagram of human visual system and neuromorphic vision using photoelectric memristors. Reproduced with permission from ref . Copyright 2022 Wiley-VCH.…”

Multi-factor-controlled ReRAM devices and their applications

“…180 This research represents a new paradigm for artificial optoelectronic synapse sensing systems and opens up an opportunity for developing low-power humanoid optoelectronic devices for artificial intelligence applications in the future. In addition, X. Shan et al developed a plasmonic photomemristive device using Ag–TiO 2 nanocomposite thin films as the functional layer of the device, 181 demonstrating a multifunctional integrating visual sensing device with low-level image preprocessing (Fig. 18c).…”

Emerging Memristive Devices for Brain-Inspired Computing and Artificial Perception

“…In artificial sensory neuron systems, near-infrared light pulses can significantly increase the spike rate. Shan et al proposed a novel plasmonic photomemristor that combines the LSPR effect with optical excitation, which can effectively improve the learning efficiency and accuracy of image recognition (Shan et al, 2022).…”