Evidence for out-of-equilibrium states in warm dense matter probed by X-ray Thomson scattering

Abstract

A recent and unexpected discrepancy between \textit{ab initio} simulations and the interpretation of a laser shock experiment on aluminum, probed by X-ray Thomson scattering (XRTS), is addressed. The ion-ion structure factor deduced from the XRTS elastic peak (ion feature) is only compatible with a strongly coupled out-of-equilibrium state. Orbital free molecular dynamics simulations with ions colder than the electrons are employed to interpret the experiment. The relevance of decoupled temperatures for ions and electrons is discussed. The possibility that it mimics a transient, or metastable, out-of-equilibrium state after melting is also suggested.

12 pages, 3 figures

References in corpus (2)

• Coupling Strength in Coulomb and Yukawa One-Component Plasmas
• Electron-ion scattering in dense multi-component plasmas: application to the outer crust of an accreting neutron star

Cited by in corpus (16)

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• Ion-ion dynamic structure factor, acoustic modes and equation of state of two-temperature warm dense aluminum
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