In this Letter, we propose and realize a novel concept for a high-peak-power highly efficient fiber amplifier in the 1.55 µm spectral range. The amplifier is based on the simultaneous utilization of Er-doped, Yb-free, and Er-Yb codoped large-mode-area fibers spliced together. Using this approach, we demonstrate the amplification of single-frequency 160 ns pulses at 1554 nm to a peak power of 3.7 kW with a pump-to-signal conversion efficiency of 23.6% relative to the launched multimode pump power at 976 nm.

中文翻译：

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高效3.7 kW峰值功率单频组合Er / Er-Yb光纤放大器

在这封信中，我们提出并实现了一种在1.55 µm频谱范围内的高峰值功率高效光纤放大器的新颖概念。该放大器基于同时使用的掺Er掺杂，无Yb掺和Er-Yb共掺大模式区域光纤。使用这种方法，我们演示了将1554 nm的单频160 ns脉冲放大到3.7 kW的峰值功率，相对于976 nm发射的多模泵浦功率，泵浦-信号转换效率为23.6％。