Ultracompact Multicore Fiber De-Multiplexer Using an Endface-Integrating Graphene Photodetector Array

The use of multicorefiber (MCF) aims to increasethefiber density with downsizedfiber systems, which is constrainedby a de-multiplexer with a large footprint that converts the MCFinto numerous single-modefibers and corresponding number ofinfrared photodetectors. In this study, we demonstrate anultracompact seven-corefiber de-multiplexer by integrating apatterned single-layer graphene (SLG) photodetector array on asinglefiber endface. An optimized electrode configuration wassuccessfully fabricated with a strongly asymmetrical structure onpatterned SLG. Owing to the efficient photocarrier separation atthe built-in electricfield across the metal-doped junction ingraphene, we realized self-powered seven-core photodetection usingthe device. Remarkably, our device exhibits a coupling-free,miniaturized device volume with zero power consumption, a high transmittance, and low manufacturing cost. This devicedownsizes traditional bulky receiver modules to the micrometer scale with an atomical thickness, which may inspire the developmentof next-generation highly integrated optical and optoelectronic systems