In this paper, we demonstrate a novel dual-pump approach to generate robust optical frequency comb with varying free spectral range (FSR) spacing in a CMOS-compatible high-Q micro-ring resonator (MRR). The frequency spacing of the comb can be tuned by an integer number FSR of the MRR freely in our dual-pump scheme. The dual pumps are self-oscillated in the laser cavity loop and their wavelengths can be tuned flexibly by programming the tunable filter embedded in the cavity. By tuning the pump wavelength, broadband OFC with the bandwidth of >180 nm and the frequency-spacing varying from 6 to 46-fold FSRs is realized at a low pump power. This approach could find potential and practical applications in many areas, such as optical metrology, optical communication, and signal processing systems, for its excellent flexibility and robustness.

中文翻译：

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具有可变FSR间隔的双泵Kerr微腔光学频率梳。

在本文中，我们演示了一种新颖的双泵方法，可在兼容CMOS的高Q微环谐振器（MRR）中产生具有变化的自由光谱范围（FSR）间距的鲁棒光学频率梳。在我们的双泵方案中，可以自由地通过MRR的整数FSR来调整梳齿的频率间隔。双泵在激光腔环路中是自激振荡的，并且可以通过对嵌入腔中的可调滤波器进行编程来灵活地调节其波长。通过调节泵浦波长，可以在低泵浦功率下实现带宽> 180 nm，频率间隔为6至46倍FSR的宽带OFC。这种方法具有出色的灵活性和鲁棒性，因此可以在许多领域找到潜在的实际应用，例如光学计量，光学通信和信号处理系统。