The Polymer Society of Korea

Abstract

To address the limitations of electrolyte-based neuromorphic devices, such as instability and fabrication incompatibility, we propose a fully solid-state photonic synapse utilizing AgBiS₂-based heterojunctions. By exploiting the intrinsic trap states and persistence photoconductive (PPC) properties of AgBiS₂, our device achieves long-term memory retention without the need for ion-gel or floating-gate structures. The incorporation of Y6 with distinct near-infrared absorption enables wavelength-selective trapping and detrapping, resulting in bidirectional and reconfigurable synaptic weight modulation. This behavior is further elucidated through a thermodynamic photo-generation trap model, offering fundamental insights into colorimetric synaptic switching under spectrally diverse stimuli. The simplified architecture and CMOS-compatible fabrication highlights its potential for scalable integration into neuromorphic photonic circuits.