Joint Theory Seminar of European XFEL, CFEL & University of Hamburg

Development of free-energy density functional methods for warm dense matter applications

by Dr Valentin V. Karasiev (Laboratory for Laser Energetics, University of Rochester)

Zoom meeting

Zoom meeting


Ab initio molecular dynamics (AIMD) simulations based on the free-energy density functional theory (DFT) in combination with the Kubo--Greenwood (KG) formulation for transport and optical properties, has proven to be a successful and key tool to understand warm-dense-matter (WDM) and high-energy density (HED) plasmas across different regimes. In this talk I present a novel DFT-based methodology for optical property calculations of warm dense matter to cover a wide range of thermodynamic conditions and photon energies including the entire x-ray range. The methodology was applied to opacity calculations of warm dense silicon plasmas and revealed a very interesting phenomenon of redshift-to-blueshift in K-L (1s → 2p) and K-edge absorptions along both isotherm and isochore, which are absent in most continuum-lowering models of traditional plasma physics. The potential for predictive DFT calculations of WDM depends crucially upon having an exchange-correlation (XC) free-energy functional accurate across temperature regimes. Furthermore we discuss development of XC density functionals with explicit temperature dependence at the meta generalized gradient approximation (meta-GGA) level of theory providing improved accuracy across the temperature regimes. Thermal meta-GGA functional provides a systematically improved accuracy of WDM simulations, as we show on example of dense Hydrogen and Helium.



Zoom link

Meeting ID: 960 0492 3285

Passcode: 216328


Organized by

Nils Brouwer