Universal Fan-in/Fan-out Solution for Few-Mode Multi-Core Fibers Using Multi-Mode Fibers

With the development of AI, the capacity demand for interconnection between computing component is increasing. As a solution has been vigorously developed in the past half of century, optical interconnection has been put forward with higher demands. Few-mode multi-core fiber (FM-MCF), a key technology within spatial division multiplexing (SDM), has consistently pushed the boundaries of single optical fiber communication capacity records. However, the non-standardized fiber design of FM-MCF poses a significant challenge in terms of multiplexing and demultiplexing. The difficulty lies in the preservation of high-order modes and mode field adaptation. To address these challenges, we propose a universal fiber-core multiplexing/demultiplexing solution for FM-MCF, leveraging multi-mode optical fiber (MMF) as a versatile bridging medium. The simulation and experimental results demonstrate excellent insertion loss and high-order mode retention capabilities. This solution offers compatibility with a wide range of FM-MCF designs, making it highly adaptable for various research applications. Furthermore, by using commercially available MMF, the solution reduces both cost and complexity, presenting a practical and scalable approach to advancing FM-MCF technology as a next-generation transmission medium for AI-driven computing systems.