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arXiv · 1003.4727

Femtosecond filamentation in air and higher-order nonlinearities

M. Kolesik·E. M. Wright·J. V. Moloney
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Abstract

According to a recent experiment, the instantaneous electronic Kerr effect in air exhibits a strong intensity dependence, the nonlinear refractive index switching sign and crossing over from a self-focusing to a de-focusing nonlinearity. A subsequent theoretical work has demonstrated that this has paradigm-changing consequences for the understanding of filamentation in air, so it is important to subject the idea of higher-order nonlinearities to stringent tests. Here we use numerical modeling to propose an experiment capable of discriminating between the standard and the new intensity-dependent Kerr-effect models.

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M. Kolesik, E. M. Wright, J. V. Moloney. 2010-03-24. Femtosecond filamentation in air and higher-order nonlinearities. https://doi.org/10.1364/ol.35.002550

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