This paper presents theoretical and experimental analysis of up-converted coherent population oscillations (Up-CPO) in semiconductor optical amplifiers (SOAs) for tunable optical phase shift applications at high frequencies. The study of Up-CPO frequency response is carried out by a small-signal analysis of a SOA modeled by two calculation sections in order to better take into account the nonlinear effects such as the SOA gain saturation. We demonstrate that we can fully determine the dynamic parameters of Up-CPO from the experimental frequency response of an optical probe signal obtained by cross-gain modulation mechanism. The Up-CPO frequency responses are measured for three SOAs with different cut-off frequencies up to 18.45 GHz. We finally validate experimentally the obtained analytical frequency responses for the three SOAs over different operating points, each characterized by the corresponding optical gain.

中文翻译：

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半导体光放大器中上变频相干粒子群振荡的两个计算部分的小信号分析和实验验证

本文介绍了用于高频可调光相移应用的半导体光放大器 (SOA) 中上变频相干布居振荡 (Up-CPO) 的理论和实验分析。Up-CPO 频率响应的研究是通过对由两个计算部分建模的 SOA 进行小信号分析来进行的，以便更好地考虑非线性效应，例如 SOA 增益饱和。我们证明我们可以从通过交叉增益调制机制获得的光学探测信号的实验频率响应中完全确定 Up-CPO 的动态参数。测量三个 SOA 的 Up-CPO 频率响应，这些 SOA 具有高达 18.45 GHz 的不同截止频率。