Researchers Develop Grazing-Incidence X-ray Platform for Real-Time Laser-Driven Surface Dynamics
Scientists have demonstrated a new experimental platform using x-ray free-electron lasers (XFELs) to simultaneously measure surface and subsurface changes in laser-irradiated materials with picosecond time resolution. The technique combines grazing-incidence small-angle x-ray scattering (GISAXS) and grazing-incidence x-ray diffraction (GID) to probe nanometer-scale depths in gold films heated above their melting point. The advance provides detailed benchmarks for theoretical models of ultrafast laser-matter interactions and has potential applications in inertial confinement fusion research.
Researchers have developed a grazing-incidence x-ray platform at an x-ray free-electron laser facility that simultaneously records time-resolved GISAXS and GID data from femtosecond laser-irradiated gold films with picosecond resolution. By adjusting the x-ray incidence angle, the technique achieves depth-selective sensitivity to tens of nanometers below the surface, allowing researchers to separately measure ultrafast changes in surface nanomorphology (correlation length and roughness) via GISAXS while GID quantifies subsurface lattice compression, grain orientation, melting, and recrystallization. The approach overcomes photon-flux limitations inherent in synchrotron-based grazing-incidence geometries, enabling more stringent experimental benchmarks for validating complex theoretical models of ultrafast laser-matter interaction and warm dense matter physics. The methodology is also well-suited for inertial confinement fusion applications, where it could visualize buried-interface perturbations and interfacial thermal resistance at micron to sub-micron scales that influence instability seeding and burn propagation.
What's missing
The study does not discuss specific quantitative results from the gold film experiments, limitations of the current depth-resolution capabilities, or timelines for application to inertial confinement fusion experiments.
What different sources said
- arXiv physicsCenter
Probing laser-driven surface and subsurface dynamics via grazing-incidence XFEL scattering and diffraction
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