Optoelectronic Synaptic Memtransistor Based on 2D SnSe/MoS₂ van der Waals Heterostructure under UV–Ozone Treatment

TLDR

Memristive switching devices that combine electrical and optical synaptic behaviors hold promise for artificial visual systems, and 2D materials with van der Waals heterostructures enable multifunctional optoelectronic devices. The study aims to develop a SnSe/MoS₂ van der Waals p‑n heterojunction memtransistor that simulates the human visual system and offers a strategy to modulate resistive switching for neuromorphic processing. A SnSe/MoS₂ p‑n heterojunction memtransistor, treated with mild UV‑ozone, provides reversible resistive switching and synaptic functionalities. The device exhibits reversible resistive switching with a ratio up to 10³, wavelength‑selective retinal‑like responses, programmable multilevel states, long‑term plasticity, and memory/logic functions, demonstrating a viable neuromorphic strategy.

Abstract

Memristive switching devices with electrically and optically invoked synaptic behaviors show great promise in constructing an artificial biological visual system. Through rational design and integration, 2D materials and their van der Waals (vdW) heterostructures can be applied to realize multifunctional optoelectronic devices. Here, a multifunctional optoelectronic synaptic memtransistor based on a SnSe/MoS2 vdW p-n heterojunction to simulate the human biological visual system is reported. By employing simple mild UV-ozone treatment, the device exhibits reversible resistive switching (RS) behavior with switching ratio up to 103 . The retina-like selective response to different input light wavelengths is activated, as well as programmable multilevel resistance states and long-term synaptic plasticity. Moreover, memory and logic functions analogous to those found in the visual cortex of the brain are performed by controlling the optical and electrical input signals. This work proposes a feasible strategy to modulate RS in vdW heterostructures for memristive devices, which show significant potential for neuromorphic processing.