Year: 2026
Type: article
Abstract: Electron-ion equilibration dynamics in samples driven into superheated states with multi-eV electron temperatures represent a fundamental process in nonequilibrium physics. A clear picture of the evolving ion temperature is essential for understanding the strength of the electron-ion coupling. However, direct, model-independent measurements of the ion temperature in laser-irradiated samples have remained experimentally elusive. Using inelastic X-ray scattering with meV-resolution in gold samples, the ion response to ultrafast heating by the hot electrons can be resolved, quantifying the electron-ion equilibration dynamics. We report measurements revealing a strongly enhanced energy transfer rate compared to that in weakly excited gold. Moreover, we obtain a quasi-constant electron-ion coupling at the highly elevated electron temperatures. These results place new constraints on electron-ion energy transfer in warm dense matter and establish a path toward quantitative benchmarking of models for nonequilibrium dynamics.
Source: Nature Communications
Authors: Travis D. Griffin, Dirk O. Gericke, Daniel Haden, Hae Ja Lee, Eric Galtier, Eric Cunningham, Dimitri Khaghani, Michael Larsen, Lennart Wollenweber, Ben Armentrout, Carson Convery, Karen Appel, Gilliss Dyer, Luke B. Fletcher, Sebastian Göde, J. B. Hastings, Jeremy Iratcabal, Emma E. McBride, Jacob Molina, Giulio Monaco, Landon Morrison, Hunter Stramel, Sameen Yunus, Ulf Zastrau, Siegfried H. Glenzer, Gianluca Gregori, Bob Nagler, Thomas G. White
Institutions: University of Nevada, Reno, European X-Ray Free-Electron Laser, University of Warwick, SLAC National Accelerator Laboratory, Columbia University, Queen's University Belfast, Princeton University, Princeton Plasma Physics Laboratory, University of Padua, University of Oxford, University of California, Merced
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W7165177336