The nonlinear propagation characteristics of multiwavelength optical signals in silicon waveguides are investigated for all-optical regeneration. Our experiment and simulation show that the multiwavelength regenerators based on silicon waveguides can be developed with a clock-pump scheme by properly setting the signal and pump power levels, ensuring that the Q-factor degradation induced by the Kerr nonlinear cross talk of the input signals is <1.0 dB and the clock-pump power is no more than the saturated input level related to the nonlinear loss. A three-wavelength regeneration experiment based on the clock-pump four-wave-mixing scheme was demonstrated in the silicon nanowire waveguide, and both the extinction ratio and Q-factor are improved by >3.0 dB for 12.5 Gbit/s on–off keying signals. The feasibility of an eight-wavelength regeneration with the clock pump is also verified by simulation.
The spectrum shift of erbium-doped magneto-optic fiber Bragg grating (Er-MFBG) induced by external magnetic fields is, for the first time, directly measured by the method of the "direct edge detection," and then the effective Verdet constant of −12.42 rad/(T·m) is determined. The theoretical results are in agreement with the experimental data. Our analysis shows the transfer characteristics of the spectrum shift to the transmission power are dependent on the state of polarization and wavelength position of probe light for a given Er-MFBG.