Windeler Matthew K R, Mecseki Katalin, Miahnahri Alan, Robinson Joseph S, Fraser James M, Fry Alan R, Tavella Franz
Opt Lett. 2019 Sep 1;44(17):4287-4290. doi: 10.1364/OL.44.004287.
New high-repetition-rate x-ray free electron lasers (XFELs) require for their operation highly reliable ultrafast laser systems with high pulse energy, high repetition rate, and high average power. In this Letter, we present high-average-power scaling of near-infrared optical parametric chirped pulse amplification (OPCPA) in potassium titanyl arsenate (KTA) with tunable center wavelengths from 1.5 to 2.0 μm. Using a three-stage amplification scheme and a kW-level InnoSlab Yb:YAG pump amplifier for the final non-collinear KTA stage, we demonstrate an amplified output power of 106.2 W at a center wavelength of 1.75 μm and 100 kHz. Idler absorption introduces a potential upper limit on the average power scaling of center wavelengths <1.70 μm. Future scaling of average power to hundreds of Watts is possible at center wavelengths ≥1.70 μm.
新型高重复频率X射线自由电子激光（XFEL）的运行需要高度可靠的超快激光系统，该系统要具备高脉冲能量、高重复频率和高平均功率。在本信函中，我们展示了钛酸氧钾（KTA）中近红外光参量啁啾脉冲放大（OPCPA）的高平均功率扩展，其中心波长在1.5至2.0μm范围内可调。采用三级放大方案，并在最终的非共线KTA级使用千瓦级的InnoSlab Yb:YAG泵浦放大器，我们在中心波长为1.75μm、重复频率为100kHz时实现了106.2W的放大输出功率。闲频光吸收对中心波长<1.70μm的平均功率扩展引入了潜在的上限。在中心波长≥1.70μm时，未来有可能将平均功率扩展至数百瓦。
