Fig. 3: Nonlinear Photoresponse of the Photonic Memristor to Incident Light Powers.

a Dark current response curves to different initial voltages. The nonlinear and memristive response through sweeping voltage loops is labeled i to iv. b Dark current variations with V ranging from −1V to +1 V after a high-voltage cycle from −40V to +40 V and back. c Displays the device’s nonlinear photocurrents under various optical stimuli, captured across a scanning voltage loop from 40 V to −40V. d The photoresponse to 631 nm light at different power levels and biases. The device showcases sensitivity to both light intensity and applied voltage. e Photoresponse over a range of wavelengths and voltages at a constant incident power. f–g The memristive photoresponses to monochromatic light at 631 nm and 640 nm under five different initial bias conditions. States are identified as 1 (−40 V), 2 (10 V), 3 (20 V), 4 (30 V), and 5 (40 V), each applied for 20 seconds during initial preprocessing. h Illustrates the photoresponses after etching the top WSe₂ layer to introduce a barrier against Pd ion migration. It effectively diminishes the memristive characteristics. This panel also compares the linear photoresponse behaviors of the modified (non-memristive) device post-chemical processing, using 631 nm, 635 nm, and 640 nm monochromatic light as stimuli. i Noise-equivalent power (NEP) and external quantum efficiency (EQE) of the device at −10V