Opt Express. 2023 Feb 13;31(4):6890-6906. doi: 10.1364/OE.480505.
We perform a beat-frequency-resolved analysis for two-dimensional electronic spectroscopy using a high-speed and stable 2D electronic spectrometer and few-cycle visible laser pulses to disentangle the vibrational coherences in an artificial fluorescent protein. We develop a highly stable ultrashort light source that generates 5.3-fs visible pulses with a pulse energy of 4.7 µJ at a repetition rate of 10 kHz using multi-plate pulse compression and laser filamentation in a gas cell. The above-5.3-fs laser pulses together with a high-speed multichannel detector enable us to measure a series of 2D electronic spectra, which are resolved in terms of beat frequency related to vibrational coherence. We successfully extract the discrete vibrational peaks behind the inhomogeneous broadening in the absorption spectra and the vibrational quantum beats of the excited electronic state behind the strong incoherent population background in the typical 2D electronic spectra.
我们使用高速稳定的二维电子光谱仪和少周期可见激光脉冲对二维电子光谱进行拍频分辨分析，以解卷入造荧光蛋白中的振动相干。我们开发了一种高度稳定的超短光源，该光源在气体池中的多板脉冲压缩和激光细丝化的作用下，产生重复率为 10 kHz 的 5.3fs 可见光脉冲，其脉冲能量为 4.7µJ。上述 5.3fs 激光脉冲和高速多通道探测器使我们能够测量一系列二维电子光谱，这些光谱可以根据与振动相干相关的拍频来分辨。我们成功地从吸收光谱中的非均匀展宽以及典型二维电子光谱中强非相干布居背景后的激发电子态的振动量子拍频中提取离散的振动峰。
