Fig. 3

Light pulse signal and data transmission decoding based on Morse code. a Schematic of data encryption transmission and decryption. b The current response of the PRM device under same electrical pulse and different light pulse duty cycle. Here 4% and 20% of the 2 kHz illumination were selected to simulate the short and long signal states for further testing. c Single PRM device data decoding of the “HBU” Morse code