Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul, 02841, Republic of Korea.
Department of Chemistry, Princeton University, Princeton, NJ, 08544, USA.
Nat Commun. 2020 Nov 27;11(1):6029. doi: 10.1038/s41467-020-19912-5.
How atoms and electrons in a molecule move during a chemical reaction and how rapidly energy is transferred to or from the surroundings can be studied with flashes of laser light. However, despite prolonged efforts to develop various coherent spectroscopic techniques, the lack of an all-encompassing method capable of both femtosecond time resolution and nanosecond relaxation measurement has hampered various applications of studying correlated electron dynamics and vibrational coherences in functional materials and biological systems. Here, we demonstrate that two broadband (>300 nm) synchronized mode-locked lasers enable two-dimensional electronic spectroscopy (2DES) study of chromophores such as bacteriochlorophyll a in condensed phases to measure both high-resolution coherent vibrational spectrum and nanosecond electronic relaxation. We thus anticipate that the dual mode-locked laser-based 2DES developed and demonstrated here would be of use for unveiling the correlation between the quantum coherence and exciton dynamics in light-harvesting protein complexes and semiconducting materials.
利用激光闪光，可以研究分子中原子和电子在化学反应过程中的运动方式，以及能量向或从周围环境传递的速度。然而，尽管人们长期努力开发各种相干光谱技术，但缺乏一种既能实现飞秒时间分辨率又能实现纳秒弛豫测量的通用方法，这阻碍了在功能材料和生物系统中研究相关电子动力学和振动相干性的各种应用。在这里，我们证明了两个宽带（>300nm）同步锁模激光器可用于对凝聚相中的细菌叶绿素 a 等发色团进行二维电子光谱（2DES）研究，以测量高分辨率相干振动谱和纳秒电子弛豫。因此，我们预计这里开发和展示的基于双锁模激光器的 2DES 将有助于揭示在光捕获蛋白复合物和半导体材料中的量子相干和激子动力学之间的相关性。
