Fig. 4: Simulation of the behavior of human visual system.

a The “learning-forgetting-relearning” process triggered by multiple light pulses. b, c Simulation of the light adaptive behavior of human visual system in 635 nm wavelength application scenario. d EPSC variations of Ta₂NiSe₅/SnS₂ device under RGB-light pulses (635, 532, and 405 nm) with various light power from 2 to 13 μW. RGB pulse conditions: 200 ms width and 200 ms interval. e EPSC distribution depending on the number of RGB-light pulses extracted from (d). f The decay of the EPSC after 30 RGB-light pulses extracted from (d). g We used the RGB-light information shown in the figure for single-point scanning imaging. For example, “R-6” represents red light pulses (635 nm) with 6 μW. The duration, interval, and quantity of all the optical are 200 ms, 200 ms, and 30, respectively. h 2D contour map of PSCs measured from Ta₂NiSe₅/SnS₂ device at different pulses and retention time conditions. All measurements were performed at a drain voltage of −3 V and a gate voltage of −5 V