Temporal diffraction by nonlinear interaction in optical fibers

Abstract
We describe an experiment in which two temporally stretched femtosecond pulses interact in a Kerr-like nonlinear medium. At high pulse energy, new, regularly spaced peaks appear in the autocorrelation of the recompressed output. The results are in quantitative agreement with numerical calculations of nonlinear propagation that show that both advanced and retarded pulses are present in the recompressed output and are comparable in duration with the input pulses. The results can be explained by drawing an analogy between four-wave mixing in real space and diffraction in the time domain.