Predicting supercontinuum pulse collisions with simulations exhibiting temporal aliasing

Abstract

Interactions between supercontinuum light pulses, produced by the propagation of rapidly sequenced ps pump laser pulses along photonic crystal fiber, result in spectral broadening which we attribute to interpulse soliton collisions. This phenomenon was measured experimentally following our observation in numerical simulations that exhibit so called ‘pulse wrap-around’ or ‘temporal aliasing’. This occurs in simulations with narrow time grids: as early parts of the supercontinuum pulse leave the computational time domain they ‘reenter’ at the beginning and so interact with later parts of the evolving SC pulse. We show that this provides an effective model to predict the experimentally observed spectral changes.