Zhao Lijuan, Pérez Lustres J Luis, Farztdinov Vadim, Ernsting Nikolaus P
Department of Chemistry, Humboldt University, Berlin, Germany.
Phys Chem Chem Phys. 2005 Apr 21;7(8):1716-25. doi: 10.1039/b500108k.
Time-resolved emission bands can be observed by simultaneous sum-frequency mixing with femtosecond near-infrared gate pulses over a wide frequency range. Using tilted gate pulses in a noncollinear geometry we achieve 80 fs time resolution and background-free measurement of upconverted spectra. All components were optimized resulting in a spectrometer for routine applications. As example we report the initial fluorescence from Coumarin 153 in acetonitrile after excitation at 400 nm. The fluorescence is modulated by nuclear coherence in the excited state which affects band width and asymmetry more than the energy gap itself.
通过在很宽的频率范围内与飞秒近红外门脉冲同时进行和频混频，可以观测到时间分辨发射带。在非共线几何结构中使用倾斜门脉冲，我们实现了80飞秒的时间分辨率以及上转换光谱的无背景测量。对所有组件进行了优化，从而得到了一款适用于常规应用的光谱仪。作为示例，我们报告了在400nm激发后，乙腈中香豆素153的初始荧光。该荧光由激发态的核相干调制，这对带宽和不对称性的影响大于对能隙本身的影响。
