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arXiv · 2010.15990

Self-focusing and self-compression of intense pulses via ionization-induced spatiotemporal reshaping

Xiaohui Gao·Bonggu Shim
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Abstract

Ionization is a fundamental process in intense laser-matter interactions, and is known to cause plasma defocusing and intensity clamping. Here, we investigate theoretically the propagation dynamics of an intense laser pulse in a helium gas jet in the ionization saturation regime, and we find that the pulse undergoes self-focusing and self-compression through ionization-induced reshaping, resulting in a manyfold increase in the laser intensity. This unconventional behavior is associated with the spatiotemporal frequency variation mediated by ionization and spatiotempral coupling. Our results illustrate a new regime of pulse propagation and open up an optics-less approach for raising the laser intensity.

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Xiaohui Gao, Bonggu Shim. 2020-10-29. Self-focusing and self-compression of intense pulses via ionization-induced spatiotemporal reshaping. https://doi.org/10.1364/ol.405575

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