Landau damping in an electron gas

Material science methods aim at developing efficient computational schemes for describing complex manybody effects and how they are revealed in experimentally measurable properties. The Bethe-Salpeter equation in the self-consistent Hartree-Fock basis is often used for this purpose, and in this paper we employ the realfrequency diagrammatic Monte Carlo framework for solving the ladder-type Bethe-Salpeter equation for the three-point vertex function (and, ultimately, for the system's polarization) to study the effect of electron-hole Coulomb scattering on Landau damping in the homogeneous electron gas. We establish how this damping mechanism depends on the Coulomb parameter rs and changes with temperature between the correlated liquid and thermal gas regimes. In a broader context of dielectric response in metals, we also present the full polarization and the typical dependence of the exchange-correlation kernel on frequency at finite momentum and temperature within the same computational framework.