Co-Stimuli-Driven 2D WSe₂ Optoelectronic Synapses for Neuromorphic Computing

Neuromorphic computing offers a promising approach to overcoming the limitations of von Neumann architecture by mimicking biological synapses. While optoelectronic synapses have demonstrated synaptic plasticity through optical and electrical stimuli, most studies rely on ambient light conditions, limiting their robustness and functional complexity. Here, a WSe₂/h-BN/SiO₂ heterostructure-based optoelectronic synapse is presented that achieves precise synaptic weight modulation through co-stimuli of electrical and optical pulses. The device exhibits enhanced paired-pulse facilitation (PPF) and long-term plasticity (LTP/LTD), demonstrating stable and linear synaptic behavior. Notably, the study systematically analyzes the effects of co-stimuli firing conditions, revealing that both the intensity of light and voltage magnitude influence synaptic weight updates. The device achieves outstanding nonlinearity, high G_max/G_min, and stable depression recovery, essential for high-performance neuromorphic computing. Furthermore, ANN-based cognitive simulations using MNIST digits validate their potential for inference tasks, demonstrating near-ideal accuracy. These findings underscore the potential of co-stimuli-driven synapses for multi-modal cognitive systems, paving the way for advanced neuromorphic architectures beyond single-species stimuli constraints.