Photoelectron tomography of electron vortices from tailored CEP-stable few-cycle and multicolour optical fields

来自定制 CEP 稳定的少周期和多色光场的电子涡流的光电子断层扫描

• 批准号: 410989756
• 负责人: Professor Dr. Matthias Wollenhaupt
• 金额: --
• 依托单位: Arbeitsgruppe Ultraschnelle Kohärente Dynamik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/410989756?language=en
• 关键词: Photoelectron; tomography; electron; vortices; tailored

Manipulating coherent light-induced electron dynamics with Carrier Envelope Phase (CEP) stable polarization-tailored femtosecond laser fields is a scientific objective at the heart of the second funding period of QUTIF.In the first funding period of QUTIF, we have implemented a supercontinuum polarization pulse shaper for the generation of tailored CEP-stable few-cycle pulses and bichromatic fields with variable frequency ratios [Opt. Express 25 (2017) 12518]. Using counterrotating circularly polarized pulse sequences in combination with photoelectron tomography, we presented the first experimental demonstration of free electron vortices from multiphoton ionization of atoms [Phys. Rev. Lett. 118 (2017) 053003] which have attracted much attention, both theoretically and experimentally.In the second funding period of QUTIF, we plan to extend our preliminary research by exploring advanced physically motivated coherent control scenarios for multiphoton ionization of model systems using polarization-tailored CEP-stable few-cycle and multicolour femtosecond laser fields. Special emphasis lies on the implementation of control scenarios to manipulate M- vs. N-photon interferences using pulse shaper-based variable frequency-ratio bichromatic fields from phase-stable supercontinuum radiation. The initial focus of our investigations will be on advanced coherent control of free electron vortices. For example, we will demonstrate CEP-sensitive bichromatic free electron vortices with an odd number of arms, including a single-armed vortex, by interference of ionic states with opposite parity, map Rydberg-type bound state dynamics and measure the ionization time of frequency mixing pathways by spectral interference in the continuum. Initially, we will validate these scenarios on quasi-one- and multi-electron systems in the perturbative regime and continue to explore these schemes in the non-perturbative and tunnel ionization regime. Three-dimensional photoelectron momentum distributions, measured by photoelectron tomography, are utilized to extract detailed information on the controlled quantum dynamics. We will refine our experimental set-up by two technical improvements: (1) the installation of an atomic / molecular beam in our photoelectron spectrometer to counteract spatial CEP-averaging by the Gouy phase and (2) the design and implementation of a ‘TWIN-shaper’, i.e. a novel polarization shaper for CEP-stable supercontinua. Combining the ‘TWIN-shaper’ to provide precise control on shape the electric field with highly differential detection by photoelectron tomography will allow us to demonstrate unprecedented manipulation of coherent electron dynamics in atoms and molecules.

利用载波包络相位 (CEP) 稳定偏振定制飞秒激光场操纵相干光感电子动力学是 QUTIF 第二资助期的核心科学目标。在 QUTIF 第一个资助期，我们实施了超连续偏振脉冲整形器，用于生成具有可变频率比的定制 CEP 稳定的少周期脉冲和双色场 [选项 Express 25 (2017) 12518]。我们利用反向旋转圆偏振脉冲序列与光电子断层扫描相结合，首次展示了原子多光子电离产生的自由电子涡流[Phys Rev. Lett. 118 (2017) 053003]。在 QUTIF 的第二个资助期，我们计划通过探索先进的物理驱动相干控制场景来扩展我们的初步研究使用偏振定制的 CEP 稳定的少周期和多色飞秒激光场进行模型系统的多光子电离 特别强调使用基于脉冲整形器的可变频率比双色来控制 M 与 N 光子干扰场景。我们研究的最初重点将是自由电子涡流的先进相干控制，例如，我们将演示 CEP 敏感的双色自由电子。具有奇数臂的涡旋，包括单臂涡旋，通过具有相反宇称的离子态的干扰，映射里德堡型束缚态动力学，并通过连续谱中的光谱干扰测量混频路径的电离时间。将在微扰状态下的准单电子和多电子系统上验证这些方案，并继续在非微扰和隧道电离状态下探索这些方案。通过光电子断层扫描测量的分布用于提取有关受控量子动力学的详细信息，我们将通过两项技术改进来改进我们的实验装置：（1）在我们的光电子能谱仪中安装原子/细化分子束以抵消空间。通过 Gouy 相进行 CEP 平均，以及 (2)“TWIN 整形器”的设计和实现，即结合了 CEP 稳定超连续谱的新型偏振整形器。 “TWIN-shaper”通过光电子断层扫描的高度差分检测来精确控制电场的形状，这将使我们能够展示对原子和分子中相干电子动力学的前所未有的操纵。