학술논문
Model Independent Electron-Ion Equilibration Rate, Debye Temperature, and Bond Strength Measurements in Warm Dense Metals with Inelastic X-Ray Scattering
Document Type
Conference
Author
Griffin, T. D.; Haden, D.; White, T.; Nagler, B.; Lee, H.-J.; Galtier, E.; Khaghani, D.; Yunus, S.; Cunningham, E.; Hastings, J.; Molina, J.; Glenzer, S.; McBride, E.; Fletcher, L.; Monaco, G.; Zastrau, U.; Appel, K.; Goede, S.; Wollenweber, L.; Gericke, D.; Gregori, G.; Descamps, A.; Armentrout, B.; Convery, M.
Source
2023 IEEE International Conference on Plasma Science (ICOPS) Plasma Science (ICOPS), 2023 IEEE International Conference on. :1-1 May, 2023
Subject
Language
ISSN
2576-7208
Abstract
When a high-intensity laser is incident on a solid target, the preferential and rapid heating of one subsystem over the other creates a highly non-equilibrium state 1;2 , These transient, high-energy-density plasmas are a precursor to warm dense matter (WDM) and serve as a testbed where we can validate quantum mechanical theories for electron-ion interactions. We have implemented a high-resolution (~50meV) X-ray scattering platform 3 , designed for use with free-electron lasers, with a resolution capable of measuring changes to the quasi-elastic Rayleigh peak. Essentially governed by Doppler broadening, the peak's width is a direct measurement of the ions' velocity distribution and corresponds to a model-independent ion temperature measurement of the plasma. We have measured the rise of the ion temperature in a variety of laser excited metallic thin films (Au, Ag, Cu, and Ti) over the first ~20 ps after irradiation, during which the ions are rapidly heated to electron volt temperatures. Useful quantities can be determined using the temporal evolution of the ion temperature; electron-ion equilibrations rates, Debye temperature, and Bond Hardening will be discussed and compared to several theoretical and computational models.