Numerical and experimental comparison of spectral broadening of femtosecond optical asymmetric pulses in a monomode fiber.
The experimental self-phase-modulation spectra of 55-fsec optical pulses after propagation along 11 mm of monomode fiber are compared with the computed spectra obtained by a numerical solution of the nonlinear wave-propagation equation. We discuss the relative importance of the pertinent additional terms (third-order-disperson, shock, and reflection terms) and the importance of an asymmetric profile of the input pulses. This asymmetry is found to be a dominant parameter in the self-phase-modulation process. No other physical effect must be used in order to explain the observed spectra, which agree well with the numerical data.
Boyer
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Franco
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