Large-Scale and Flexible Optical Synapses for Neuromorphic Computing and Integrated Visible Information Sensing Memory Processing

TLDR

Optoelectronic synapses that integrate synaptic and optical‑sensing functions offer energy‑efficient neuromorphic computing for visual processing, learning, recognition, and memory, but existing devices still require electric stimulation for bidirectional weight updates, limiting speed, bandwidth, and integration density. The study proposes a two‑terminal optical synapse built on a wafer‑scale pyrenyl graphdiyne/graphene/PbS quantum‑dot heterostructure that emulates excitatory and inhibitory synaptic behaviors optically. The device employs a simple wafer‑scale heterostructure architecture that endows the optical synapse with robust flexibility for wearable electronics and enables an integrated visible‑information‑sensing memory‑processing array capable of real‑time detection, in‑situ image memorization, and distinction tasks. The optical synapse exhibits a linear, symmetric conductance‑update trajectory with numerous low‑noise states, enabling accurate, fault‑tolerant pattern recognition even under bending, and demonstrates logic functions, associative learning, and an integrated memory‑processing system, marking a significant advance toward optogenetics‑inspired neuromorphic computing and adaptive parallel processing for wearable electronics.

Abstract

Optoelectronic synapses integrating synaptic and optical-sensing functions exhibit large advantages in neuromorphic computing for visual information processing and complex learning, recognition, and memory in an energy-efficient way. However, electric stimulation is still essential for existing optoelectronic synapses to realize bidirectional weight-updating, restricting the processing speed, bandwidth, and integration density of the devices. Herein, a two-terminal optical synapse based on a wafer-scale pyrenyl graphdiyne/graphene/PbS quantum dot heterostructure is proposed that can emulate both the excitatory and inhibitory synaptic behaviors in an optical pathway. The simple device architecture and low-dimensional features of the heterostructure endow the optical synapse with robust flexibility for wearable electronics. This optical synapse features a linear and symmetric conductance-update trajectory with numerous conductance states and low noise, which facilitates the demonstration of accurate and effective pattern recognition with a strong fault-tolerant capability even at bending states. A series of logic functions and associative learning capabilities have been demonstrated by the optical synapses in optical pathways, significantly enhancing the information processing capability for neuromorphic computing. Moreover, an integrated visible information sensing memory processing system based on the optical synapse array is constructed to perform real-time detection, in situ image memorization, and distinction tasks. This work is an important step toward the development of optogenetics-inspired neuromorphic computing and adaptive parallel processing networks for wearable electronics.