Du Xueyuan, Zhang Hanwei, Ma Pengfei, Xiao Hu, Wang Xiaolin, Zhou Pu, Liu Zejin
Opt Lett. 2015 Nov 15;40(22):5311-4. doi: 10.1364/OL.40.005311.
In this Letter, we demonstrate a kilowatt (kW) level high-power fiber laser amplifier with a clear sign of spectral-broadening-free property. The high-power fiber lasing is realized by employing a master oscillator power-amplifier (MOPA) configuration, seeded by a temporally stable random fiber laser (RFL) that utilizes Raman amplification and random distributed feedback from a long passive fiber. The output power reaches 1.03 kW with a 1070 nm wavelength and an optical-to-optical efficiency of 74.6%. Despite the typical nonlinear spectral broadening in most traditional MOPA systems, the output spectral linewidth is well maintained during the whole high-power amplification process. The suppressed linewidth broadening in the spectral domain during high-power amplification is significant for further power scaling, spectral beam combination, and other applications that require narrow-linewidth high-power lasing.
在本信函中，我们展示了一种千瓦（kW）级的高功率光纤激光放大器，它具有明显的无光谱展宽特性。高功率光纤激光通过采用主振荡功率放大（MOPA）结构实现，由一个时间稳定的随机光纤激光器（RFL）作为种子源，该随机光纤激光器利用拉曼放大和来自长无源光纤的随机分布反馈。输出功率在波长为1070 nm时达到1.03 kW，光光效率为74.6%。尽管在大多数传统MOPA系统中存在典型的非线性光谱展宽，但在整个高功率放大过程中，输出光谱线宽得到了很好的保持。在高功率放大过程中光谱域中线宽展宽的抑制对于进一步的功率缩放、光谱光束合成以及其他需要窄线宽高功率激光的应用具有重要意义。
