Clérouin Jean, Robert Grégory, Arnault Philippe, Ticknor Christopher, Kress Joel D, Collins Lee A
CEA, DAM, DIF 91297 Arpajon, France.
Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Jan;91(1):011101. doi: 10.1103/PhysRevE.91.011101. Epub 2015 Jan 20.
A recent and unexpected discrepancy between 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.
本文探讨了从头算模拟与通过X射线汤姆逊散射（XRTS）探测的铝激光冲击实验解释之间最近出现的意外差异。从XRTS弹性峰（离子特征）推导出的离子-离子结构因子仅与强耦合非平衡态兼容。采用离子比电子冷的轨道自由分子动力学模拟来解释该实验。讨论了离子和电子解耦温度的相关性。还提出了它模拟熔化后瞬态或亚稳态非平衡态的可能性。
