The dual-comb coherent anti-Stokes Raman scattering (CARS) technique has been proposed and developed for many years with various applications. It maps the spectral information to the time domain and resolves Raman peaks by scanning the relative delay of the pulse pair. One main drawback of this method is the low duty cycle. The span of scanning is far larger than needed, leading to a massive waste of time and energy. In this Letter, a dual-comb fiber laser system with fast repetition modulation ability is proposed and demonstrated. It can detect the relative delay via an asymmetric sum-frequency-mixing method and flip the repetition frequency difference at the exact time to increase the duty cycle by several hundred times. Consequently, it is expected that the detection efficiency is greatly enhanced compared to traditional dual-comb systems for CARS measurements.

中文翻译：

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重复频率调制光纤激光器用于相干抗斯托克斯拉曼散射

已经提出并开发了具有多种应用的双梳相干反斯托克斯拉曼散射（CARS）技术。它将频谱信息映射到时域，并通过扫描脉冲对的相对延迟来解析拉曼峰。这种方法的一个主要缺点是占空比低。扫描的跨度远远超过所需的范围，导致大量的时间和精力浪费。在这封信中，提出并演示了具有快速重复调制能力的双梳状光纤激光系统。它可以通过非对称和频混合方法检测相对延迟，并在准确的时间翻转重复频率差，从而将占空比提高数百倍。所以，