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arXiv · 1604.02453

A critical assessment of models of pair-interactions and screening used in analyzing recent warm-dense matter (WDM) experiments

L. Harbour·M. W. C. Dharma-wardana·D. D. Klug·L. J. Lewis
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Abstract

Ultra-fast laser experiments yield increasingly reliable data on warm-dense matter (WDM), but rely on entrenched simplistic theoretical models. We re-analyze two topical experiments, avoiding (i) {\it ad hoc} core-repulsion models, (ii) "Yukawa screening" models and (iii) electron-ion equilibrium assumptions. An accurate, rapid density-functional neutral-pseudoatom model coupled to a hyper-netted-chain (HNC) equation with a bridge term is used to compute structure factors, X-Ray scattering, compressibility, phonons and resistivity. Electronic-structure codes are used to confirm the calculations. The Yukawa and core-repulsion models are shown to be misleading.

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L. Harbour, M. W. C. Dharma-wardana, D. D. Klug, L. J. Lewis. 2016-04-10. A critical assessment of models of pair-interactions and screening used in analyzing recent warm-dense matter (WDM) experiments. https://doi.org/10.1103/physreve.94.053211

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