Study of cross-phase modulation and free-carrier dispersion in silicon photonic wires for Mamyshev signal regenerators

A numerical study on Mamyshev signal regeneration realized on silicon photonic wires is reported. Unlike fiber-optics Mamyshev regenerators employing cross-phase modulation, silicon photonic wires have to include two-photon absorption and the two-photon-absorption-induced free-carrier effect. By well adjusting time delay between the co-propagating signal and clock pulses, both cross-phase modulation and free-carrier dispersion could induce nonlinear wavelength shift, which is essential for signal recovery in the Mamyshev regeneration scheme. A simulation result shows the quality factor of signal eye diagram improved by more than 4 dB for Return-to-Zero signals with pulse width 10 ps, peak power 6.5 W, and operation speed 10 Gbit/s through a 1-cm silicon photonic wire.