We have implemented polarization-resolved fluorescence lifetime measurement through stimulated emission based pump-probe technique, which promises much higher temporal resolution (~4 ps) than conventional time-correlated single-photon counting. The depolarization of ATTO 647N fluorescent dye is resolved through anisotropy fluorescence lifetime measurements, with variable time delay introduced between the pump and the probe beams. Importantly, the polarization anisotropy measurement and the corresponding rotational correlation time characterization of the fluorescent dyes are carried out at various temperatures. We have also demonstrated the need of high temporal resolution via hetero Förster energy transfer (Hetero-FRET) through the interaction between the gold nanorods (GNRs) and the fluorescent dye ATTO 647N. Notably, our results compare highly favorably with conventional TCSPC method, which is rather limited in temporal resolution, for the above characterization. Additionally, this technique is applicable even under ambient light while being very cost-effective and robust.

中文翻译：

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通过受激发射实现高时间分辨率和偏振分辨的荧光寿命测量。

我们已经通过基于激发发射的泵浦探针技术实现了偏振分辨的荧光寿命测量，与常规的时间相关单光子计数相比，它具有更高的时间分辨率（〜4 ps）。通过各向异性荧光寿命测量可解决ATTO 647N荧光染料的去极化问题，并在泵浦光和探测光束之间引入可变的时间延迟。重要的是，在各种温度下进行荧光染料的偏振各向异性测量和相应的旋转相关时间表征。我们还证明了通过金纳米棒（GNR）与荧光染料ATTO 647N之间的相互作用，需要通过异质Förster能量转移（Hetero-FRET）实现高时间分辨率的需求。值得注意的是 对于上述表征，我们的结果与常规TCSPC方法相比非常有利，后者在时间分辨率上受到很大限制。另外，该技术甚至在环境光下也适用，同时具有很高的成本效益和坚固性。