Lead‐Free Perovskites‐Based Photonic Synaptic Devices with Logic Functions

Abstract Lead halide perovskites have shown great potential in photonic synaptic devices owing to their notable optical properties. However, the inherent toxicity of lead and complex configuration of the device hinder the further development of perovskites‐based photonic synaptic devices. Here, lead‐free double perovskite Cs₂AgSbBr₆ is first used to fabricate photonic synaptic devices. The photonic synaptic device with a simple structure exhibits decent reproducibility and stability. By tuning external light signals, photonic synaptic devices based on Cs₂AgSbBr₆ can mimic primary synaptic behaviors, such as excitatory postsynaptic current, paired pulse facilitation, short‐term memory (STM), long‐term memory (LTM), the transfer between STM and LTM, and the “learning‐forgetting‐relearning” process. Furthermore, the temperature effect on the learning and memory process is investigated. Importantly, logic functions of “OR” and “AND” operations are realized. This work suggests the great potential of Cs₂AgSbBr₆ in future neuromorphic computation.