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arXiv · 1607.05476

Resonantly enhanced filamentation in gases

J. Doussot·G. Karras·F. Billard·P. Béjot·O. Faucher
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Abstract

In this Letter, a low-loss Kerr-driven optical filament in Krypton gas is experimentally reported in the ultraviolet. The experimental findings are supported by ab initio quantum calculations describing the atomic optical response. Higher-order Kerr effect induced by three-photon resonant transitions is identified as the underlying physical mechanism responsible for the intensity stabilization during the filamentation process, while ionization plays only a minor role. This result goes beyond the commonly-admitted paradigm of filamentation, in which ionization is a necessary condition of the filament intensity clamping. At resonance, it is also experimentally demonstrated that the filament length is greatly extended because of a strong decrease of the optical losses.

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J. Doussot, G. Karras, F. Billard, P. Béjot, O. Faucher. 2016-07-19. Resonantly enhanced filamentation in gases. https://arxiv.org/abs/1607.05476

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