Landau Damping in an Electron Gas

I. S. Tupitsyn; N. V. Prokof'ev

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arXiv · 2311.05611

Landau Damping in an Electron Gas

I. S. Tupitsyn·N. V. Prokof'ev

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Abstract

Material science methods aim at developing efficient computational schemes for describing complex many-body effects and how they are revealed in experimentally measurable properties. Bethe-Salpeter equation in the self-consistent Hartree-Fock basis is often used for this purpose, and in this paper we employ the real-frequency diagrammatic Monte Carlo framework for solving the ladder-type Bethe-Salpeter equation for the 3-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 $r_s$ 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.

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I. S. Tupitsyn, N. V. Prokof'ev. 2023-11-09. Landau Damping in an Electron Gas. https://arxiv.org/abs/2311.05611

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