Early-Time Reshaping of Laser-Induced Plasma Profiles

Ivan Ostrovsky; Gilad Hurvitz; Soumitra Hazra; Sharly Fleischer

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arXiv · 2608.22545

Early-Time Reshaping of Laser-Induced Plasma Profiles

Ivan Ostrovsky·Gilad Hurvitz·Soumitra Hazra·Sharly Fleischer

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Abstract

Laser-induced plasmas are primarily characterized by their temporal density decay. Using time-resolved transverse optical diffractometry, we reveal their concurrent spatial evolution, demonstrating pronounced broadening and flattening during the first 200 ps following ionization. This non-self-similar evolution arises from the local density dependence of electron-ion recombination, without particle transport. Exploiting the continuum of initial densities within a single plasma disc, we experimentally reconstruct an effective, time-dependent local recombination law over a broad density range. Applied locally to independently measured initial plasma profiles, this kinetic map quantitatively predicts their subsequent evolution. These results are relevant to transient diffractive optics, plasma-based optical elements and waveguides, and the development of laser-induced plasmas as platforms for gas-phase THz plasmonics.

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Ivan Ostrovsky, Gilad Hurvitz, Soumitra Hazra, Sharly Fleischer. 2026-08-23. Early-Time Reshaping of Laser-Induced Plasma Profiles. https://arxiv.org/abs/2608.22545

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