Abstract

Weakly-coupled mode division multiplexing (MDM) techniques supporting intensity modulation and direct detection (IM/DD) have attracted great attention for capacity enhancement of short-reach applications such as optical interconnections, for which mode multiplexers/demultiplexers (MMUX/MDEMUX) with low insertion loss (IL) and modal crosstalk are the key components. In this paper, we firstly propose the design method for degenerate–mode-selective couplers (DMSC) with side-polishing processing. Three kinds of DMSCs for different degenerate linearly-polarized (LP) modes (LP₁₁, LP₂₁ and LP₃₁) in a weakly-coupled few-mode fiber (FMF) are designed. Then a pair of MMUX and MDEMUX consisting of cascaded mode-selective couplers (MSC) and DMSCs for all the 5 LP modes of the FMF are fabricated with side-polishing processing. The measurement results show that the MMUX and MDEMUX achieve low back-to-back IL lower than 5.3 dB for all the 5 modes. Finally, stable digital-signal-processing (DSP)-free 5-mode IM/DD MDM transmission utilizing conventional optical modules over 10-km FMF are successfully demonstrated. The proposed low-IL MMUX/MDEMUX is scalable to support more modes and can promote the practical application of MDM techniques.

Low-modal-crosstalk orthogonal combine reception for degenerate modes in IM/DD MDM transmission

Jian Cui, Yuyang Gao, Shuailuo Huang, Jinyi Yu, Lei Shen, Lei Zhang, Changkun Yan, Liubo Yang, Ruichun Wang, Yongqi He, Zhangyuan Chen, and Juhao Li
Opt. Express 31(5) 8586-8594 (2023)

Weakly-coupled 4-mode step-index FMF and demonstration of IM/DD MDM transmission

Tao Hu, Juhao Li, Dawei Ge, Zhongying Wu, Yu Tian, Lei Shen, Yaping Liu, Su Chen, Zhengbin Li, Yongqi He, and Zhangyuan Chen
Opt. Express 26(7) 8356-8363 (2018)

Prototype system for real-time IM/DD MDM transmission based on multiple-ring-core FMF and degenerate-mode-selective reception

Yuyang Gao, Dawei Ge, Jian Cui, Junchi Jia, Yongqi He, Zhangyuan Chen, Guifang Li, and Juhao Li
Opt. Express 27(26) 38281-38288 (2019)

Broadband mode-selective couplers based on tapered side-polished fibers

Kun Zhang, Pengjun Wu, Jiangli Dong, Dawei Du, Zuoxin Yang, Cheng Xu, Heyuan Guan, Huihui Lu, Wentao Qiu, Jianhui Yu, and Zhe Chen
Opt. Express 29(13) 19690-19702 (2021)

Low-CD weakly-coupled FMF for short-reach IM/DD MDM transmission

Ruiting Cheng, Qichen He, Mingqing Zuo, Yu Yang, Chuyu Peng, Zhangyuan Chen, Yongqi He, and Juhao Li
Opt. Express 31(20) 31937-31945 (2023)