In two-dimensional electronic spectroscopy (2DES), precise control of the arrival time of ultrashort laser pulses is critical to correlating the molecular states that are accessed in the experiment. In this work, we demonstrate a 2D electronic spectrometer design with an interferometric phase stability of ∼λ/250 at 600 nm. First, we present a new method for controlling pulse delay times based on transmission through pairs of optical flats rotated perpendicular to the beam propagation direction. Second, the calibration methods required to achieve adequate timing precision are also reported. Compared to existing designs using translating wedges, the rotating optical flats can achieve equivalent optical delay with a shorter path length in glass, reducing errors due to spectral dispersion of the broadband laser pulses used in 2DES. Our approach presents a simple, low-cost technique for multidimensional optical spectroscopy that is capable of resolving complex light-induced dynamics.

中文翻译：

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使用旋转光学平面的二维电子光谱。

在二维电子光谱（2DES）中，精确控制超短激光脉冲的到达时间对于关联在实验中访问的分子状态至关重要。在这项工作中，我们演示了一种二维电子光谱仪设计，其在600 nm处的干涉相稳定性为λ/ 250。首先，我们提出了一种新的方法来控制脉冲延迟时间，该方法基于通过垂直于光束传播方向旋转的成对光学平板的传输来控制脉冲延迟时间。其次，还报告了实现足够的定时精度所需的校准方法。与使用平移楔形的现有设计相比，旋转的光学平板可以在较短的玻璃路径中实现等效的光学延迟，从而减少了2DES中使用的宽带激光脉冲的光谱色散所带来的误差。