Photon-Energy-Gated Carrier Accumulation in Ordered Core–Shell Nanowires for Neuromorphic Photodetection and Memory

Abstract

Engineering semiconductor heterojunctions is a pivotal research frontier for developing next-generation optoelectronic devices, particularly for neuromorphic computing. However, performing precise, stimulus-selective control over interfacial carrier dynamics to unlock advanced memory and logic functions remains a significant challenge. Herein, we unveil a novel “photon-energy-gated selective carrier accumulation” mechanism within macroscopically ordered ZnO/Ga2O3 core–shell nanowire heterojunctions, governed by the Type-I band alignment at the heterointerface. This unique architecture, fabricated via a super-aligned carbon nanotube template, not only boosts the UV photoresponsivity by 78-fold compared to pure ZnO counterparts but also enables a remarkable wavelength-selective activation of persistent photoconductivity. Harnessing this optically switchable memory effect, we demonstrate its application in optoelectronic synaptic devices, and we also prove its potential in physical reservoir computing system, achieving a high classification accuracy of 87.9% on the Fashion - Modified National Institute of Standards and Technology (F-MNIST) dataset. This study provides a new paradigm for designing intelligent optoelectronic devices by precisely manipulating interfacial carrier dynamics, opening promising avenues for in-sensor computing and advanced photonic memory.