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textit{Ab Initio} Path Integral Monte Carlo Results for the Dynamic Structure Factor of Correlated Electrons: From the Electron Liquid to Warm Dense Matter

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 نشر من قبل Michael Bonitz
 تاريخ النشر 2018
  مجال البحث فيزياء
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The accurate description of electrons at extreme density and temperature is of paramount importance for, e.g., the understanding of astrophysical objects and inertial confinement fusion. In this context, the dynamic structure factor $S(mathbf{q},omega)$ constitutes a key quantity as it is directly measured in X-ray Thomson (XRTS) scattering experiments and governs transport properties like the dynamic conductivity. In this work, we present the first textit{ab initio} results for $S(mathbf{q},omega)$ by carrying out extensive path integral Monte Carlo simulations and developing a new method for the required analytic continuation, which is based on the stochastic sampling of the dynamic local field correction $G(mathbf{q},omega)$. In addition, we find that the so-called static approximation constitutes a promising opportunity to obtain high-quality data for $S(mathbf{q},omega)$ over substantial parts of the warm dense matter regime.



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