Sensory Adaptation and Neuromorphic Phototransistors Based on CsPb(Br<sub>1–<i>x</i></sub>I<sub><i>x</i></sub>)<sub>3</sub> Perovskite and MoS<sub>2</sub> Hybrid Structure
Seongin Hong, Seung Hee Choi, Jongsun Park, Hocheon Yoo, Joo Youn Oh, E. H. Hwang, Dae Ho Yoon, Sunkook Kim
Abstract
perovskite, we introduce neuromorphic phototransistors that emulate human sensory adaptation. The phototransistor based on a hybrid structure of perovskite and transition-metal dichalcogenide (TMD) emulates the sensory adaptation in response to a continuous light stimulus, similar to the neural system. The underlying mechanism for the sensory adaptation is the halide segregation of the mixed halide perovskites. The phase separation under visible-light illumination leads to the segregation of I and Br into separate iodide- and bromide-rich domains, significantly changing the photocurrent in the phototransistors. The devices are reversible upon the removal of the light stimulation, resulting in near-complete recovery of the photosensitivity before the phase segregation (sensitivity recovery of 96.65% for 5 min rest time). The proposed phototransistor based on the perovskite-TMD hybrid structure can be applied to other neuromorphic devices such as neuromorphic photonic devices, intelligent sensors, and selective light-detecting image sensors.