Ma Pengfei, Zhou Pu, Wang Xiaolin, Ma Yanxing, Su Rongtao, Liu Zejin
Opt Express. 2013 Dec 2;21(24):29666-78. doi: 10.1364/OE.21.029666.
In this manuscript, the influence of perturbative phase noise on active coherent polarization beam combining (CPBC) system is studied theoretically and experimentally. By employing a photo-detector to obtain phase error signal for feedback loop, actively coherent polarization beam combining of two 20 W-level single mode polarization-maintained (PM) fiber amplifiers are demonstrated with more than 94% combining efficiency. Then the influence of perturbative phase noise on active CPBC system is illustrated by incorporating a simulated phase noise signal in one of the two amplifiers. Experimental results show that the combining efficiency of the CPBC system is susceptible to the frequency or amplitude of the perturbative phase noise. In order to ensure the combining efficiency of the unit of CPBC system higher than 90%, the competence of our active phase control module for high power operation is discussed, which suggests that it could be worked at 100s W power level. The relationship between residual phase noise of the active controller and the normalized voltage signal of the photo-detector is developed and validated experimentally. Experimental results correspond exactly with the theoretically analyzed combining efficiency. Our method offers a useful approach to estimate the influence of phase noise on CPBC system.
在本论文中，从理论和实验两方面研究了微扰相位噪声对有源相干偏振光束合成（CPBC）系统的影响。通过使用光电探测器获取反馈回路的相位误差信号，实现了两个20W级单模保偏（PM）光纤放大器的有源相干偏振光束合成，合成效率超过94%。然后，通过在两个放大器之一中加入模拟相位噪声信号，阐述了微扰相位噪声对有源CPBC系统的影响。实验结果表明，CPBC系统的合成效率对微扰相位噪声的频率或幅度很敏感。为确保CPBC系统单元的合成效率高于90%，讨论了我们的有源相位控制模块在高功率运行方面的能力，结果表明它可以在100sW功率水平下工作。建立了有源控制器的残余相位噪声与光电探测器归一化电压信号之间的关系，并通过实验进行了验证。实验结果与理论分析的合成效率完全吻合。我们的方法为评估相位噪声对CPBC系统的影响提供了一种有用的途径。
