A parabolic pulse generator based on non-reciprocal nonlinear optical fiber loop mirror is proposed. When an incident triangular optical pulse is split into two branches of the loop mirror, two coherent light fields with linear intensity profile are counter-propagated in the interferometer and suffer different nonlinear phase shift caused by self-phase modulation. Because the intensity of interference field is determined by the amplitudes and phase relationship between two coherent lights, the interference result gives parabolic pulse. This concept is verified by theoretical analysis and simulation. In the experiment, tunable bright and dark parabolic pulses with repetition frequencies of 8, 9, and 10 GHz are simultaneously generated, which agree with the theoretical expectation well and exhibit large operation bandwidth.

中文翻译：

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基于非线性光纤环镜的抛物线脉冲产生

提出了一种基于非互易非线性光纤环镜的抛物线脉冲发生器。当入射的三角光脉冲分裂为环形镜的两个分支时，具有线性强度分布的两个相干光场在干涉仪中反向传播，并受到由自相位调制引起的不同非线性相移。由于干涉场的强度是由两束相干光的幅度和相位关系决定的，干涉结果给出了抛物线脉冲。这一概念得到了理论分析和仿真的验证。实验中同时产生了重复频率为8、9、10GHz的可调亮暗抛物线脉冲，与理论预期吻合良好，工作带宽大。