Temporal manipulation of light propagation via cross-intensity modulation in unbalanced fiber Mach-Zehnder interferometers

We theoretically propose and experimentally demonstrate an approach to achieve temporal manipulation of light propagation via cross-intensity modulation (XIM) effect in an unbalanced fiber Mach-Zehnder interferometer (MZI). By changing the optical loss indices (which can also be gain indices theoretically) discrepantly in the two branches of the MZI, we can obtain the largest time shifts at the minima of the transmission frequency spectrum, while there shows no time shifts at the maxima. This scheme provides a flexibility of ultra-wide bandwidth operation both on optical wavelength and modulation frequency.