Kefer Oskar, Kolesnichenko Pavel V, Buckup Tiago
Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany.
Rev Sci Instrum. 2024 Feb 1;95(2). doi: 10.1063/5.0186915.
Broadband implementation of two-dimensional electronic spectroscopy (2DES) is a desirable goal for numerous research groups, yet achieving it presents considerable challenges. An effective strategy to mitigate these challenges is the utilization of two-color approaches, effectively broadening the spectral bandwidth accessible with 2DES. Here, we present a simple approach to include multi-color configurations based on adjustable mirror mounts. This enables seamless toggling between single-color, two-color, and transient 2DES within the same spectroscopic apparatus, which is benchmarked on two common laser dyes, Rhodamine 6G and Nile blue. Upon mixing the dyes, single-color 2DES shows overlapping signals, whereas a high selectivity toward Nile blue responses is maintained in two-color and transient 2DES, owing to the fully resonant excitation that is spectrally shifted relative to the detection window. This method is readily implemented in other setups with similar experimental layouts and can be used as a simple solution to overcome existing bandwidth limitations. With the inclusion of transient 2DES, additional insights into excited-state processes can be gained due to its increased sensitivity toward excited-state coherences.
对众多研究团队而言，二维电子光谱（2DES）的宽带实现是一个理想目标，但要实现这一目标面临着诸多挑战。减轻这些挑战的一个有效策略是采用双色方法，有效地拓宽2DES可获取的光谱带宽。在此，我们提出一种基于可调镜架纳入多色配置的简单方法。这使得在同一光谱仪器内能够在单色、双色和瞬态2DES之间无缝切换，我们以两种常见激光染料罗丹明6G和尼罗蓝为基准对此进行了测试。混合染料后，单色2DES显示出重叠信号，而在双色和瞬态2DES中对尼罗蓝响应保持了高选择性，这是由于相对于检测窗口在光谱上发生了位移的完全共振激发。该方法易于在具有类似实验布局的其他装置中实施，并且可以用作克服现有带宽限制的简单解决方案。通过纳入瞬态2DES，由于其对激发态相干性的更高灵敏度，可以获得对激发态过程的更多见解。
