Time-Dependent Density-Functional-Theory Studies of Nonlocal Electron Stopping Range in ICF Plasmas

Nonlocal electron transport is crucial for understanding laser-target coupling for laser direct drive (LDD) inertial confinement fusion (ICF) simulations. Current models for the nonlocal electron mean free path in radiation-hydrodynamic codes are based on plasma-physics models developed decades ago; improvements are needed to accurately predict the electron conduction in LDD simulations of ICF target implosions [1]. We have utilized time-dependent density-functional-theory (TD-DFT) in both the Kohn Sham [2] and the orbital free [3] approach to calculate the electron stopping power in both polystyrene and DT plasmas in a wide range of densities and temperatures relevant to LDD ICF. Compared to analytical models, the TD-DFT calculations in polystyrene indicated a lower stopping power and a higher mean free path for nonlocal electrons [4]; current TD-DFT calculations will show how electron stopping in hot dense DT compares to traditional plasma models. Based on these TD-DFT results, a global analytical model for electron stopping range in CH has been developed as a function of plasma conditions and the nonlocal electron kinetic energy. A corresponding model for the DT case will be developed. By implementing both models into the 1-D radiation-hydrodynamic code, LILAC [5], to perform simulations of LDD ICF implosions, we will show the significant implications of this TD-DFT based mean-free-path model to ICF simulations.



[1] V. N. Goncharov et al., Phys. of Plasmas 13, 012702 (2006).

[2] A. J. White, et al., J. Phys.: Condens. Matter 34, 17 (2022).

[3] Y. H. Ding et al., Phys. Rev. Lett. 121, 145001 (2018); A. J. White et al., Phys. Rev. B 98, 144302 (2018).

[4] K. A. Nichols et al. (under review).

[5] J. Delettrez, et al., Phys. Rev. A 36, 3926 (1987).