Near-Infrared Optical Synapses Based on Multilayer MoSe2 Moire Superlattice for Artificial Retina

Near-infrared (NIR) synaptic devices have attracted great attention in the field of NIR vision sensors due to their highly parallel sensing and memory functions, which emulate the basic biomimetic behaviors of the human visual system. However, it is a great challenge for the 2D material to achieve NIR light response and integration, which obstructs the progress of NIR synaptic devices. Hence, a two-terminal NIR synaptic device based on a multilayer MoSe2 moir & eacute; superlattice is reported. The moire structure dominated by interlayer excitons significantly enhances the interlayer coupling of multilayer MoSe2, resulting in a narrower band gap nearly to that of bulk to achieve NIR light response and broadband absorption from 240 nm to 1700 nm. The existence of Se vacancies in MoSe2 moire superlattice makes the device show the fundamental synaptic performance. Furthermore, a 10x10 integrated retinal morphologic device array is constructed. Under the 100 s light pulse stimulation of 1060 nm, the pattern obtained after attenuation of 50 s still has a memory level of 14.84%, reflecting the excellent storage function under NIR illumination. This research opens up a new avenue for the realization of NIR artificial retina and bionic eye based on 2D materials.

Automated summary

A two-terminal NIR synaptic device based on a multilayer MoSe2 moiré superlattice is reported in this study, demonstrating strong sensing and storage functions similar to the human visual system. The interlayer coupling of multilayer MoSe2 is significantly enhanced by the moiré structure, enabling NIR light response and absorption. This research opens up new possibilities for the realization of NIR artificial retina and bionic eye based on 2D materials.