Ultracompact Multicore Fiber De-Multiplexer Using an Endface-Integrating Graphene Photodetector Array
Yifeng Xiong, Haotian Xu, Yushu Wang, Chenhui Wu, Zixuan Ding, Mengmeng Chen, Yufeng Hao, Ye Chen, Fei Xu
Abstract
The use of multicore fiber (MCF) aims to increase the fiber density with downsized fiber systems, which is constrained by a de-multiplexer with a large footprint that converts the MCF into numerous single-mode fibers and corresponding number of infrared photodetectors. In this study, we demonstrate an ultracompact seven-core fiber de-multiplexer by integrating a patterned single-layer graphene (SLG) photodetector array on a single fiber endface. An optimized electrode configuration was successfully fabricated with a strongly asymmetrical structure on patterned SLG. Owing to the efficient photocarrier separation at the built-in electric field across the metal-doped junction in graphene, we realized self-powered seven-core photodetection using the device. Remarkably, our device exhibits a coupling-free, miniaturized device volume with zero power consumption, a high transmittance, and low manufacturing cost. This device downsizes traditional bulky receiver modules to the micrometer scale with an atomical thickness, which may inspire the development of next-generation highly integrated optical and optoelectronic systems.