Dual-Mode Devices Integrating Photodetection and Optoelectronic Synaptic Plasticity Based on Pb(Zr,Ti)O3 Films

Abstract

The separation of photodetectors and optoelectronic synapses within artificial visual systems not only increases the design complexity, but also results in high energy consumption. In this work, we demonstrate a dual-mode device based on a ferroelectric Pb(Zr,Ti)O3 (PZT) thin film that combines photosensing and synaptic plasticity in a single device. Under zero bias, the device is operated as a self-powered photodetector, exhibiting a responsivity of 35.7 µA/W and a detectivity of 2.60×106 Jones. When an external bias of 0.1 V is applied, the device exhibits synaptic behaviors, including short-term plasticity and learn-forget-relearn dynamics due to the trapping and detrapping of the oxygen vacancies in the films. This bias-tunable dual functionality provides a promising route toward developing energy-efficient, highly integrated optoelectronic-neuromorphic hardware.