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arXiv · 2112.02376

Extended model for optimizing high-order harmonic generation in absorbing gases

Balázs Major·Katalin Varjú
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Abstract

We report on an extended version of the one-dimensional model proposed by Constant \emph{et al.} [Phys. Rev. Lett 82(8), 1668 (1999)] to study phase matching of high-order harmonic generation in absorbing and dispersive medium. The model - expanded from zeroth to first order - can be used with media having a pressure profile varying linearly with propagation length. Based on the new formulas, the importance of having a generation medium that ends abruptly with a steep pressure gradient for achieving high flux is highlighted. In addition to further rule-of-thumb guidelines for harmonic-flux optimization, it is shown that having a steep increase of pressure in the beginning of the medium increases harmonic flux, while it also decreases the required medium length to reach the absorption-limited maximum.

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Balázs Major, Katalin Varjú. 2022-01-06. Extended model for optimizing high-order harmonic generation in absorbing gases. https://doi.org/10.1088/1361-6455%2Fac3fbe

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