Ab initio data for the uniform electron gas at warm dense matter conditions*

Further progress in the field of warm dense matter (WDM) requires accurate data on the electron component. I summarize our recent results on computing ab inito thermodynamic data for the uniform electron gas (UEG) that cover the whole temperature-density range and arbitrary spin polarizations [1]. The results are based on a combination or two novel quantum Monte Carlo (PIMC) methods (Permutation blocking PIMC and configuration PIMC) which avoids the notorious fermion sign problem, without invoking uncontrolled approximations such as the fixed node approximation. Furthermore, a new finite-size correction scheme has been developed that allows to compute thermodynamic data in the thermodynamic limit without loss of accuracy. The result is an analytical parametrization of the exchange–correlation free energy that is the key input for the simulation of real warm dense matter applications, e.g., via thermal density functional theory.
In the second part I outline novel extensions of our simulations to achieve the first ab initio data for the static density response, the static local field correction and the dyamic structure factor for the warm dense electron gas. [1] T. Dornheim et al., Phys. Reports 744 (2018)