Advanced Electric Lasers Branch, Air Force Research Laboratory, Kirtland Air Force Base, New Mexico 87117, USA.
Opt Lett. 2011 Jul 15;36(14):2641-3. doi: 10.1364/OL.36.002641.
The Brillouin gain characteristics of a Yb-doped polarization-maintaining photonic crystal fiber possessing a segmented acoustic profile are investigated using a pump-probe technique. The concentrations of fluorine, aluminum, and germanium in two regions of the core were selected, such that the corresponding Brillouin shifts were sufficiently separated to allow for the introduction of a temperature profile along the fiber for further stimulated Brillouin scattering suppression. By using a cutback technique to measure loss, we estimated the Brillouin gain coefficient to be 1.2×10(-11) m/W. Despite differences in the concentration levels of dopants between the two segments, there was no evidence of a development of an optical interface. When this fiber was utilized in a counterpumped amplifier configuration, close to 500 W of near-diffraction-limited single-frequency output was obtained.
采用泵浦-探测技术研究了掺镱保偏光子晶体光纤的布里渊增益特性，该光纤具有分段声谱。选择芯部两个区域的氟、铝和锗浓度，使得相应的布里渊频移足够分离，以便沿光纤引入温度分布，进一步抑制受激布里渊散射。通过使用回退技术测量损耗，我们估计布里渊增益系数为 1.2×10(-11) m/W。尽管两段之间掺杂剂的浓度水平存在差异，但没有出现光学界面发展的迹象。当将这种光纤用于反向泵浦放大器配置中时，获得了接近衍射极限的单频输出功率近 500 W。
