RP ProPulse — Numerical Simulation of Pulse Propagation

Example Case: Nonlinear Pulse Compression

Here, we consider the nonlinear compression of pulses. First, the pulses are spectrally broadened by the nonlinearity of a fiber; at the same time, the pulse duration increases somewhat due to chromatic dispersion. After the fiber, a dispersive compressor is used to obtain near-bandwidth-limited pulses with a correspondingly shorter duration.

RP ProPulse is actually designed for pulse propagation in resonators, but we can consider a certain length of fiber as corresponding to one resonator round trip. (In some cases, the RP Fiber Power software is better suited for fiber applications.)

resonator: ring
* FiberPiece:
  GDD = GDD_f * dL, SPM = gamma_f * dL
resonator end

external at 0:
* Compressor: compress [order = 2, goal = maxpeak]
  { optimized dispersion for maximum peak power }
external end

The dispersive compressor is numerically optimized for maximum peak power of the pulses. The diagram below also shows the amount of group delay dispersion (GDD) used for the compressor. Interestingly, for a longer fiber piece, less GDD is required. This is due to the increased pulse bandwidth, which makes the pulses more sensitive to chromatic dispersion.

(back to the list of example cases)