National Research Council of Canada, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.
Joint Attosecond Science Laboratory, National Research Council and University of Ottawa, 100 Sussex Drive, Ottawa, ON K1A 0R6, Canada.
Science. 2017 Jun 16;356(6343):1150-1153. doi: 10.1126/science.aam8393.
Electrons detached from atoms or molecules by photoionization carry information about the quantum state from which they originate, as well as the continuum states into which they are released. Generally, the photoelectron momentum distribution is composed of a coherent sum of angular momentum components, each with an amplitude and phase. Here we show, by using photoionization of neon, that a train of attosecond pulses synchronized with an infrared laser field can be used to disentangle these angular momentum components. Two-color, two-photon ionization via a Stark-shifted intermediate state creates an almost pure f-wave with a magnetic quantum number of zero. Interference of the f-wave with a spherically symmetric s-wave provides a holographic reference that enables phase-resolved imaging of the f-wave.
通过光致电离从原子或分子中脱离的电子携带有关其起源的量子态以及它们被释放到的连续态的信息。通常，光电子动量分布由角动量分量的相干和组成，每个分量都有幅度和相位。在这里，我们通过使用氖的光致电离表明，可以使用与红外激光场同步的阿秒脉冲序列来解缠这些角动量分量。通过斯塔克移动的中间态的双色双光子电离产生具有磁量子数为零的几乎纯 f 波。f 波与球对称 s 波的干涉提供了全息参考，从而能够对 f 波进行相分辨成像。
