Electron-ion equilibration in superheated gold
Abstract
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.
Article Details
Authors (28)
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