Gu Zhimu, He Le, Yin Xiaoke, Liu Shaokun, Li Wenzhen, Xing Yingbin, Dai Nengli, Li Jinyan
Opt Express. 2024 Feb 26;32(5):7564-7573. doi: 10.1364/OE.513787.
Cladding-pumped multicore erbium-doped fiber is an important element for future spatial division multiplexing (SDM) amplification. We propose an M-type erbium-doped multicore fiber to achieve high-efficiency SDM amplification. The performance of cladding-pumped erbium-doped fiber with a central refractive index depression has been investigated, and the M-type fiber has better amplification performance than conventional fibers by reducing the signal mode overlap with the doped region. The experiment results show that the M-type 4-core erbium-doped fiber has a gain improvement of 2.8 dB compared with conventional 4-core fiber. The pump conversion efficiency (PCE) has been enhanced from 4.47% to 8.01%. For a 7.0 W pump power at 976 nm, the M-type fiber exhibits an average gain of 20.0 dB and an average noise fiber of 6.8 dB at the L-band. The core-to-core gain variation is less than 1.6 dB.
包层泵浦多芯掺铒光纤是未来空分复用（SDM）放大的重要元件。我们提出一种M型掺铒多芯光纤以实现高效SDM放大。研究了具有中心折射率凹陷的包层泵浦掺铒光纤的性能，通过减少信号模式与掺杂区域的重叠，M型光纤比传统光纤具有更好的放大性能。实验结果表明，与传统四芯光纤相比，M型四芯掺铒光纤的增益提高了2.8 dB。泵浦转换效率（PCE）从4.47%提高到了8.01%。对于976 nm处7.0 W的泵浦功率，M型光纤在L波段的平均增益为20.0 dB，平均噪声系数为6.8 dB。芯间增益变化小于1.6 dB。
