Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Nat Commun. 2018 Jun 28;9(1):2519. doi: 10.1038/s41467-018-04927-w.
Coherent two-dimensional (2D) optical spectroscopy has revolutionized our ability to probe many types of couplings and ultrafast dynamics in complex quantum systems. The dynamics and function of any quantum system strongly depend on couplings to the environment. Thus, studying coherent interactions for different environments remains a topic of tremendous interest. Here we introduce coherent 2D electronic mass spectrometry that allows 2D measurements on effusive molecular beams and thus on quantum systems with minimum system-bath interaction and employ this to identify the major ionization pathway of 3d Rydberg states in NO. Furthermore, we present 2D spectra of multiphoton ionization, disclosing distinct differences in the nonlinear response functions leading to the ionization products. We also realize the equivalent of spectrally resolved transient-absorption measurements without the necessity for acquiring weak absorption changes. Using time-of-flight detection introduces cations as an observable, enabling the 2D spectroscopic study on isolated systems of photophysical and photochemical reactions.
相干二维（2D）光学光谱学极大地提高了我们探测复杂量子系统中多种耦合和超快动力学的能力。任何量子系统的动力学和功能都强烈依赖于与环境的耦合。因此，研究不同环境下的相干相互作用仍然是一个非常感兴趣的话题。在这里，我们引入相干二维电子质谱学，它允许在扩散分子束上进行二维测量，从而对系统与环境的相互作用最小的量子系统进行测量，并利用它来确定 NO 中 3d 里德伯态的主要电离途径。此外，我们还展示了多光子电离的二维光谱，揭示了导致电离产物的非线性响应函数的明显差异。我们还实现了等效的光谱分辨瞬态吸收测量，而无需获取微弱的吸收变化。使用飞行时间检测引入了阳离子作为可观测物，使光物理和光化学反应的孤立系统的 2D 光谱研究成为可能。
