Abstract
The characteristics of pulse trapping by use of ultrashort soliton pulses in optical fibers across the zero-dispersion wavelength are analyzed both experimentally and numerically. The spectrogram of pulse trapping is observed by use of the cross-correlation frequency-resolved optical gating technique, and the phenomenon of pulse trapping is confirmed directly. The pulse trapping is numerically analyzed by use of the coupled strict nonlinear Schrödinger equations, and the numerical results are in good agreement with the experimental ones. It is clarified that the pulse trapping results from the sequential cross-phase modulation by the Raman-shifted soliton pulse.