论文标题
通过连续的泵浦探针延迟扫描,高敏荧光检测的多维电子光谱
High-sensitivity Fluorescence-Detected Multidimensional Electronic Spectroscopy Through Continuous Pump-probe Delay Scan
论文作者
论文摘要
与常规方法相比,多维电子光谱中的无背景荧光检测有望高灵敏度。在这里,我们探讨了多维电子光谱的灵敏度极限。我们提出了一个基于可见的白光连续体的荧光检测的多维电子光谱仪。为了证明灵敏度,我们报告了室温在光密度下激光染料中振动量子相干的二维相干图,比传统方法低2-3个数量级。通过沿光学相干时间轴的偏置采样的组合以及在每个时间步长的等待时间t维度的快速扫描来实现这种高灵敏度。声学相调制和相位敏感的锁定检测的结合,即使在最低的OD处,也可以同时收集室温振动波袋的转换和非重复信号以及室温振动波袋的测量。还展示了通过连续泵送扫描方法的灵活性来实现的替代性数据收集方案。
Background-free fluorescence detection in multidimensional electronic spectroscopy promises high sensitivity compared to conventional approaches. Here we explore the sensitivity limits of multidimensional electronic spectroscopy. We present a fluorescence-detected multidimensional electronic spectrometer based on a visible white-light continuum. As a demonstration of sensitivity, we report room temperature two-dimensional coherence maps of vibrational quantum coherences in a laser dye at optical densities ~2-3 orders of magnitude lower than conventional approaches. This high sensitivity is enabled by a combination of biased sampling along the optical coherence time axes and a rapid scan of the waiting time T dimension at each time step. A combination of acousto-optic phase modulation and phase-sensitive lock-in detection enables simultaneous collection of rephasing and non-rephasing signals and measurements of room temperature vibrational wavepackets even at the lowest ODs. Alternative faster data collection schemes, enabled by the flexibility of continuous pump-probe scanning approach, are also demonstrated.