Krebs Bennet S, Tulsky Vasily, Kazak Lev, Zabel Michael, Bauer Dieter, Tiggesbäumker Josef
Institute of Physics, University of Rostock, 18059 Rostock, Germany.
Department "Life, Light and Matter", University of Rostock, 18059 Rostock, Germany.
J Phys Chem Lett. 2022 Feb 17;13(6):1526-1532. doi: 10.1021/acs.jpclett.2c00110. Epub 2022 Feb 8.
Magnesium atoms fully embedded in helium nanodroplets are exposed to two-color laser pulses, which trigger multiphoton above-threshold ionization (ATI). This allows exemplary study of the contribution of a dense, neutral, and finite medium on single electron propagation. The angular-resolved photoelectron spectra show striking differences with respect to results obtained on free atoms. Scattering of the individual Mg photoelectrons, when traversing the neutral helium environment, causes the angular distribution to become almost isotropic. Furthermore, the appearance of higher-energy electrons is observed, indicating the impact of the droplet on the concerted emission process. Phase-of-the-phase spectroscopy, however, reveals a marked loss in the 2ω-ω phase dependence of the electron signal. Taking into account sideband formation on a quantitative level, a Monte Carlo simulation which includes laser-assisted electron scattering can reproduce the experimental spectra and give insights into the strong-field-induced electron emission from disordered systems.
完全嵌入氦纳米液滴中的镁原子被双色激光脉冲照射，从而引发多光子阈上电离（ATI）。这使得能够对致密、中性且有限的介质对单电子传播的贡献进行典型研究。角分辨光电子能谱显示出与在自由原子上获得的结果有显著差异。单个镁光电子在穿过中性氦环境时的散射，导致角分布几乎变得各向同性。此外，还观察到了更高能量电子的出现，这表明液滴对协同发射过程的影响。然而，相位分辨光谱揭示了电子信号在2ω - ω相位依赖性方面有明显损失。在定量层面考虑边带形成的情况下，包含激光辅助电子散射的蒙特卡罗模拟能够重现实验光谱，并深入了解无序系统中强场诱导的电子发射。
