Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Phys Rev Lett. 2013 Jul 12;111(2):023005. doi: 10.1103/PhysRevLett.111.023005. Epub 2013 Jul 9.
In strong-field light-matter interactions, the strong laser field dominates the dynamics. However, recent experiments indicate that the Coulomb force can play an important role as well. In this Letter, we have studied the photoelectron momentum distributions produced from noble gases in elliptically polarized, 800 nm laser light. By performing a complete mapping of the three-dimensional electron momentum, we find that Coulomb focusing significantly narrows the lateral momentum spread. We find a surprisingly sensitive dependence of Coulomb focusing on the initial transverse momentum distribution, i.e., the momentum at the moment of birth of the photoelectron. We also observe a strong signature of the low-energy structure in the above threshold ionization spectrum.
在强场光物质相互作用中，强激光场主导着动力学过程。然而，最近的实验表明，库仑力也可以起到重要的作用。在这篇快报中，我们研究了椭圆偏振 800nm 激光光场中惰性气体产生的光电子动量分布。通过对三维电子动量进行完全映射，我们发现库仑聚焦显著缩小了横向动量分布。我们发现库仑聚焦对初始横向动量分布的依赖性非常敏感，即光电子产生瞬间的动量。我们还观察到阈上电离谱中的低能结构的强烈特征。
