Lüttig Julian, Mueller Stefan, Malý Pavel, Krich Jacob J, Brixner Tobias
Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague, Czech Republic.
J Phys Chem Lett. 2023 Aug 24;14(33):7556-7573. doi: 10.1021/acs.jpclett.3c01694. Epub 2023 Aug 17.
Transient absorption and coherent two-dimensional spectroscopy are widely established methods for the investigation of ultrafast dynamics in quantum systems. Conventionally, they are interpreted in the framework of perturbation theory at the third order of interaction. Here, we discuss the potential of higher-(than-third-)order pump-probe and multidimensional spectroscopy to provide insight into excited multiparticle states and their dynamics. We focus on recent developments from our group. In particular, we demonstrate how phase cycling can be used in fluorescence-detected two-dimensional spectroscopy to isolate higher-order spectra that provide information about highly excited states such as the correlation of multiexciton states. We discuss coherently detected fifth-order 2D spectroscopy and its power to track exciton diffusion. Finally, we show how to extract higher-order signals even from ordinary pump-probe experiments, providing annihilation-free signals at high excitation densities and insight into multiexciton interactions.
瞬态吸收光谱和相干二维光谱是研究量子系统中超快动力学的广泛应用的方法。传统上，它们是在相互作用的三阶微扰理论框架内进行解释的。在此，我们讨论高于三阶的泵浦-探测光谱和多维光谱在深入了解激发多粒子态及其动力学方面的潜力。我们重点关注我们团队的最新进展。特别是，我们展示了如何在荧光检测二维光谱中使用相位循环来分离高阶光谱，这些光谱提供了有关高激发态（如多激子态的相关性）的信息。我们讨论了相干检测的五阶二维光谱及其追踪激子扩散的能力。最后，我们展示了如何甚至从普通的泵浦-探测实验中提取高阶信号，在高激发密度下提供无湮灭信号并深入了解多激子相互作用。
