Few-Mode Erbium-Doped Fiber with Three-Layer Center-Recessed Doping for Gain Equalization

• DOI: 10.3390/s25072010
• Publication Date: 2025-03-24T10:21:38Z
• Authors: Shengchen Bao; Yu Cheng; Yi Tang; Ming Chen; Shijie Deng; Libo Yuan
• Keywords: Mode (computer interface); Erbium; Center (category theory)

We propose a design method for few-mode erbium-doped fiber (FM-EDF) incorporating stratified doping. In the simulation design, FM-EDF effectively reduces differential mode gain (DMG) through utilization of Simulations indicate that at an input signal power -30 dBm, designed achieves DMG less than 0.5 dB across five spatial modes spanning entire C-band (1530-1570 nm) and exceeds 20 within range 1530-1560 nm. Additionally, experiments using unidirectional pumping demonstrate full-band greater dB, with maximum approaching 30 <1 in three modes. summary, proposed enhances efficiency reliability long-distance transmission optical communication networks, making it suitable high-capacity systems as well sensing systems.