High-order amplitude regularization of an optical pulse train using a power-symmetric NOLM with adjustable contrast

In this letter, we demonstrate high-quality amplitude regularization of an optical pulse train using a novel nonlinear optical loop mirror design, whose switching relies on nonlinear polarization evolution. Thanks to the possibility to adjust the switching contrast, second-order amplitude regularization is experimentally demonstrated using the proposed scheme. An overall suppression of about 20 dB of the initial fluctuation over all frequencies is obtained.