Electron-ion equilibration in superheated gold
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.
Authors
- G. Monaco (ORCID: https://orcid.org/0000-0003-2497-6422)
- L. B. Fletcher (ORCID: https://orcid.org/0000-0002-7120-7194)
- B. Armentrout (ORCID: https://orcid.org/0000-0003-1907-7959)
- Michael Larsen (ORCID: https://orcid.org/0000-0002-5172-5891)
- Landon Morrison
- Karen Appel (ORCID: https://orcid.org/0000-0002-2902-2102)
- G. Gregori (ORCID: https://orcid.org/0000-0002-4153-0628)
- G. Dyer (ORCID: https://orcid.org/0000-0001-9755-9780)
- D. O. Gericke (ORCID: https://orcid.org/0000-0001-6797-9004)
- S. H. Glenzer (ORCID: https://orcid.org/0000-0001-9112-0558)
- Eric Galtier (ORCID: https://orcid.org/0000-0002-0396-285X)
- Daniel Haden (ORCID: https://orcid.org/0000-0001-8288-664X)
- Bob Nagler (ORCID: https://orcid.org/0009-0002-5736-7842)
- Travis D. Griffin
- Thomas G. White (ORCID: https://orcid.org/0000-0002-3865-4240)
- Jeremy Iratcabal
- Dimitri Khaghani (ORCID: https://orcid.org/0000-0002-5139-2310)
- L. Wollenweber (ORCID: https://orcid.org/0000-0002-6934-1108)
- Hae Ja Lee (ORCID: https://orcid.org/0000-0002-4035-5637)
- U. Zastrau (ORCID: https://orcid.org/0000-0002-3575-4449)
- Eric Cunningham (ORCID: https://orcid.org/0000-0002-0976-4416)
- E. E. McBride (ORCID: https://orcid.org/0000-0002-8821-6126)
- Sameen Yunus (ORCID: https://orcid.org/0009-0001-0135-8472)
- J. B. Hastings
- Sebastian Göde
- Carson Convery (ORCID: https://orcid.org/0009-0000-6857-6047)
- Hunter Stramel
- Jacob Molina
Institutions
- Queen's University Belfast (GB)
- University of Nevada, Reno (US)
- University of California, Merced (US)
- Princeton University (US)
- Princeton Plasma Physics Laboratory (US)
- Istituto Nazionale di Fisica Nucleare, Galileo Galilei Institute for Theoretical Physics (IT)
- SLAC National Accelerator Laboratory (US)
- University of Warwick (GB)
- University of Oxford (GB)
- Columbia University (US)
- European X-Ray Free-Electron Laser (DE)
Publication Details
- Journal
- Nature Communications
- Published
- 2026-06-18
- DOI
- https://doi.org/10.1038/s41467-026-74346-9
- Primary Topic
- Ion-surface interactions and analysis
- Type
- article
- Field-Weighted Citation Impact
- 0.00