We report on the experimental generation of high-quality Optical Frequency Combs (OFCs) at low repetition rates in an externally-injected gain-switched semiconductor laser using a Step-Recovery Diode (SRD) as the pulsing source. The use of an SRD as the electrical pulse generator allows us to produce high-quality OFCs with over 900 comb tones spaced by 100 MHz. Through experimental measurements, supported by simulations, the timing jitter of the electrical source has been demonstrated to impact the quality of the generated OFCs giving rise to a non-uniform Carrier-to-Noise Ratio which is higher around the injection and reduces with decreasing frequency. Nevertheless, comparing the OFC quality obtained using an SRD with those obtained with a costly pulse pattern generator, we conclude, that despite the slightly degraded OFC quality, the use of SRDs could reduce the cost, size and footprint of the equipment required for low repetition rate OFC generation.

我们报告了使用步进恢复二极管（SRD）作为脉冲源的，在外部注入的增益开关半导体激光器中以低重复率进行的高品质光学频率梳（OFC）的实验生成。将SRD用作电脉冲发生器使我们能够生产高质量的OFC，其间隔超过100 MHz的900多个梳齿。通过实验测量和仿真支持，已证明电源的定时抖动会影响所产生的OFC的质量，从而导致载噪比不均匀，在注入附近会更高，随频率降低而降低。不过，将使用SRD获得的OFC质量与使用昂贵的脉冲模式发生器获得的OFC质量进行比较，我们得出的结论是，尽管OFC质量略有下降，