Dynamic behavior of frequency combs in frequency-shifting loops

摘要

The understanding of frequency-shifting loops' (FSLs) transient response is fundamental for their implementation in microwave photonic systems. We developed a numerical model, enabling us to describe the specific dynamics of the frequency comb generated in a FSL seeded by a CW laser. The model, based on laser rate equations, predicts the temporal evolution of the power of the individual comb lines during on/off cycles of the injection power, for FSLs operating below the lasing threshold. To prove the validity of the model, we performed experimental measurements of the power of the individual comb lines with time. Numerical simulations based on the model, for different gain media and pumping rates, are in excellent agreement with the experimental results. This paper provides guidance for the concrete implementation of FSLs for microwave photonic applications. (C) 2020 Optical Society of America