A high repetition-rate, few-cycle light pulse is of great importance due to its potential for a variety of applications, including two-dimensional infrared spectroscopy and time-resolved imaging of molecular structures, which benefit from its ultrabroadband spectrum and ultrashort pulse duration. The generation of an ultrabroadband coherent spectrum is one of the frontiers of ultrafast optics, and accessing such few-cycle pulses is presently under active exploration. Here, we demonstrate a simple yet effective pulse synthesizer. It is based on two continuous-wave (cw) injection-seeded high-repetition-rate optical parametric amplification systems and the following self-phase-modulation dominated spectra-broadening processes. The combined spectrum spans from 1250 to 1670 nm, and a near Fourier-transform-limited 3.9-cycle (19.2 fs) synthesized pulse with a central wavelength of 1470 nm is obtained accordingly.

中文翻译：

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由两个连续波注入种子光学参量放大器在53 MHz的相干合成产生3.9周期脉冲

高重复频率，少周期的光脉冲非常重要，这是因为它具有广泛的应用潜力，包括二维红外光谱和分子结构的时间分辨成像，这得益于其超宽带光谱和超短脉冲持续时间。超宽带相干光谱的产生是超快光学的前沿之一，目前正在积极探索访问这种少数周期脉冲的方法。在这里，我们演示了一种简单而有效的脉冲合成器。它基于两个连续波（cw）注入播种的高重复率光学参量放大系统，以及以下以自相位调制为主的频谱扩展过程。合并后的光谱范围从1250到1670 nm，以及接近傅里叶变换的3.9周期（19。