We propose a method for improving the imaging depth of two-photon excitation microscopy using correlated ultrafast intensity fluctuations within pulses. As a proof of principle, we experimentally demonstrate local control of two-photon excitation by using the ultrafast intensity cross-correlation generated by high-gain parametric down-conversion. We show that only the fluorescence intensity emitted from deep inside the fluorescent dye solution can be modulated by harnessing the correlation at ultrashort time scales. It is expected that the influence of the background photons can be suppressed by applying this technique to the two-photon excitation microscopy.

中文翻译：

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通过相关的超快强度波动来局部控制双光子激发的荧光

我们提出了一种使用脉冲内相关的超快强度波动来提高双光子激发显微镜成像深度的方法。作为原理的证明，我们通过使用高增益参数下转换产生的超快速强度互相关，通过实验证明了对双光子激发的局部控制。我们表明，通过利用超短时间尺度上的相关性，只能调制从荧光染料溶液内部深处发出的荧光强度。期望通过将该技术应用于双光子激发显微镜可以抑制背景光子的影响。