Few-femtosecond resolved imaging of laser-driven nanoplasma expansion. (1st April 2022)

• Record Type: Journal Article
• Authors: Peltz, C; Powell, J A; Rupp, P; Summers, A; Gorkhover, T; Gallei, M; Halfpap, I; Antonsson, E; Langer, B; Trallero-Herrero, C; Graf, C; Ray, D; Liu, Q; Osipov, T; Bucher, M; Ferguson, K; Möller, S; Zherebtsov, S; Rolles, D; Rühl, E; Coslovich, G; Coffee, R N; Bostedt, C; Rudenko, A; Kling, M F; Fennel, T
• Is Part Of: New journal of physics. Volume 24:Number 4(2022)
• Publication Date: 2022-04-01
• Subjects: coherent diffractive imaging -- nanoplasma expansion -- time-resolved diffraction -- strong-field ionization; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/ac5e86
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: The free expansion of a planar plasma surface is a fundamental non-equilibrium process relevant for various fields but as-yet experimentally still difficult to capture. The significance of the associated spatiotemporal plasma motion ranges from astrophysics and controlled fusion to laser machining, surface high-harmonic generation, plasma mirrors, and laser-driven particle acceleration. Here, we show that x-ray coherent diffractive imaging can surpass existing approaches and enables the quantitative real-time analysis of the sudden free expansion of laser-heated nanoplasmas. For laser-ionized SiO2 nanospheres, we resolve the formation of the emerging nearly self-similar plasma profile evolution and expose the so far inaccessible shell-wise expansion dynamics including the associated startup delay and rarefaction front velocity. Our results establish time-resolved diffractive imaging as an accurate quantitative diagnostic platform for tracing and characterizing plasma expansion and indicate the possibility to resolve various laser-driven processes including shock formation and wave-breaking phenomena with unprecedented resolution.