Few-Layer Phosphorene-Decorated Microfiber for All-Optical Thresholding and Optical Modulation

Phosphorene, mono/few-layered black phosphorous with advantages of tunable energy bandgaps and strong light-matter interaction, is fabricated by electrochemical intercalation with large area (approximate to 3 mu m) and controllable thickness (mainly four layers). Thanks to the direct gap and resonant absorption of four-layer phosphorene at the telecommunication band, all-optical thresholding and optical modulation are demonstrated for optical communications by using few-layer phosphorene-decorated microfibers. This device is experimentally verified as an efficient noise suppressor that can enhance the signal-to-noise ratio and reshape the deteriorated signal pulse, and also as an optical modulator that can switch the signal on/off by pumping light. The findings, as the first prototypic device of all-optical thresholding and optical modulation, might facilitate the development of phosphorene-based optical communication technologies.