Roberts Adam, Shivaram Niranjan, Xu Lei, Sandhu Arvinder
Department of Physics and College of Optical Sciences, University of Arizona, Tucson, AZ 85721, USA.
Opt Express. 2009 Dec 21;17(26):23894-902. doi: 10.1364/OE.17.023894.
We demonstrate the key role played by the spatial characteristics and focusing conditions of a femtosecond multi-cycle laser pulse in optimization of filament output for the purpose of obtaining compressed light pulses in the few-cycle regime. We find that for a given beam profile and focal parameters, driving the filament with energy above a certain limiting value can negatively impact pulse compression. However, for a given energy, a smaller and cleaner input beam mode obtained by using a hard aperture can substantially improve the pulse compression ability. In addition, we show that a larger focal volume can assist in creation of a shorter output pulse.
我们展示了飞秒多周期激光脉冲的空间特性和聚焦条件在优化丝状输出以获得几周期范围内的压缩光脉冲方面所起的关键作用。我们发现，对于给定的光束轮廓和聚焦参数，用高于某个极限值的能量驱动丝状会对脉冲压缩产生负面影响。然而，对于给定的能量，通过使用硬孔径获得的更小且更纯净的输入光束模式可以显著提高脉冲压缩能力。此外，我们表明更大的焦体积有助于产生更短的输出脉冲。
