Advanced Electric Laser Branch, Air Force Research Laboratory, 3550 Aberdeen Avenue SE, Kirtland Air Force Base, New Mexico 87117, USA.
Opt Lett. 2010 Sep 15;35(18):3114-6. doi: 10.1364/OL.35.003114.
We demonstrate stimulated Brillouin scattering (SBS) suppression in a Yb-doped fiber amplifier by seeding with a combination of broad- and single-frequency laser beams that are separated sufficiently to suppress four-wave mixing and to allow for efficient laser gain competition between the two signals. In the experiment, a monolithic fiber configuration was used. With appropriate selection of seed power ratio, we were able to generate single-frequency 1064 nm light with a slope efficiency of 78% while simultaneously suppressing the backscattered Stokes light. We discuss scalability to high power wherein a large thermal gradient can be induced at the output end of the fiber via quantum defect heating, leading to an SBS suppression factor comparable to counterpumping.
我们通过用组合的宽频和单频激光种子来演示掺镱光纤放大器中的受激布里渊散射（SBS）抑制，该组合的激光种子被分离得足够远，以抑制四波混频，并允许两个信号之间进行有效的激光增益竞争。在实验中，我们使用了一种单片光纤结构。通过适当选择种子功率比，我们能够以 78%的斜率效率产生单频 1064nm 光，同时抑制背向斯托克斯光。我们讨论了向高功率扩展的问题，其中可以通过量子缺陷加热在光纤的输出端产生大的热梯度，导致与反向泵送相当的 SBS 抑制因子。
