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arXiv · 2610.11494

Laser fragmentation in liquid - constructing a generic reaction map

Anton Plech·Yogesh Pokhrel·Meike Tack·Matteo Levantino·Sven Reichenberger
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Abstract

Excitation of absorbing colloids in liquid by pulsed laser irradiation creates highly non-equilibrium states of matter that relax via defined pathways of thermal and non-thermal dissipation channels. The structural fingerprint of these channels can be probed by ultrafast {\it in situ} x-ray scattering methods and classified as a function of temporal delay of excitation excitation density, or specifically laser fluence. We study the example of photo-excitation of a gold colloid by picosecond laser pulses at the interband absorption band at 400 nm in water. By quantifying lattice temperature, crystalline fraction, particle sizes and the structural response of the water around the nanoparticles a reaction map is constructed that allows to pinpoint heating, particle melting, water bubble formation and finally particle fragmentation to form nanoclusters of predominant sizes of < 3 nm for applications in theranostics, photonics or catalysis.

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Anton Plech, Yogesh Pokhrel, Meike Tack, Matteo Levantino, Sven Reichenberger. 2026-10-08. Laser fragmentation in liquid - constructing a generic reaction map. https://arxiv.org/abs/2610.11494

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