7 fs超快强激光驱动Ar原子产生支持单个阿秒脉冲的高次谐波连续谱

采用脉冲宽度为7 fs，脉冲能量为0．4mJ的超快强激光脉冲与气体盒子中Ar原子作用获得了高次谐波截止区连续谱，并发现当驱动激光稳定在不同的载波包络相位时，高次谐波的谱结构、谱调制深度和连续谱的带宽都有很大区别。在某些载波包络相位时获得了平滑的连续谱，调制深度小于17％，连续带宽达10eV，从而支持时域上获得变换极限500as的单个阿秒脉冲。

Generation of 5 fs, 0.7 mJ pulses at 1 kHz through cascade filamentation

Two-cycle optical pulses with duration of 5 fs and energy of 0.7 mJ have been generated at 1 kHz by compressing the 38 fs laser pulses from a carrier-envelope phase (CEP) controlled Ti:sapphire laser system through a cascade filamentation compression technique. A simple and effective method is developed to suppress multiple filament formation and stabilize a single filament by inserting a soft aperture with an appropriate diameter into the driving laser beam prior to focusing, resulting in an excellent compressed beam quality. The good beam quality and potentially higher peak power make this ultrashort laser pulse source a significant tool for high-field physics applications. (C) 2007 Optical Society of America.

7.3 W国产单频光纤放大器

报道了一种MOPA式国产单频光纤放大器。该放大器采用连续波单频激光器作为主振荡器，采用我国自行设计和制造的大模场面积掺Yb双包层光纤作为功率放大器，在波长1064 nm处实现了最高7.3 W的连续激光输出，斜率效率为39%，光－光转换效率为26%。此外，对光谱特性及放大的自发发射的抑制也进行了探讨。

7.3 W of single-frequency output power at 2.09 μm from an Ho:YAG monolithic nonplanar ring laser

Single-frequency output power of 7.3 W at 2.09 mu m from a monolithic Ho:YAG nonplanar ring oscillator (NPRO) is demonstrated. Resonantly pumped by a Tm-doped fiber laser at 1.91 mu m, the Ho:YAG NPRO produces 71% of slope efficiency with respect to absorbed pump power and nearly diffraction-limited output with a beam quality parameter of M-2 approximate to 1.1. (c) 2008 Optical Society of America