Dense electron-gas response at any degeneracy

Abstract

An exact expression for the linear response function of the dense electron gas valid at any temperature is worked out in the ring (RPA) approximation. The T=0 and T=∞ limits reproduce the already known results. It is used to explain the longitudinal oscillations and the screening around a test charge. The latter is either Thomas–Fermi-like or Friedel-like according to the values of the parameters.

Very low velocity ion slowing down in binary ionic mixtures: Charge- and mass-asymmetry effects

“…Moreover, the present dielectric formulation albeit restricted to a dense and classical electron fluid, could be easily extended to partially Fermi degenerate situations of obvious practical interest, by introducing the corresponding @ Þ 0 Fried-Conte extension [12,13].…”

Dielectric function of dense plasmas, their stopping power, and sum rules

“…We point out the seminal paper of Gouedard and Deutsch [25] and the paper of Arista and Brandt [26], who managed to rewrite the RPA dielectric function in a way that, at least in the 1980s, was more suitable for calculations. The high-frequency asymptotic behavior of the Lindhard DF at high and low temperatures was studied in [25,26] in detail. Recently, the Mermin model was extended to include, along the density conservation, the energy and momentum conservation laws [13,14].…”

“…II A but with −1 TCP (k,0) now being the static value of the TCP IDF, the f -sum rule, and the TCP fourth loss function power moment, which takes into account the electron-ion correlations (25) [4,5]:…”

“…The presence of the correction (25) to the fourth moment implies that if we apply the Mermin model to a two-component plasma using the mixing rule [79], both SSFs S ee (q) and S ii (q) will be involved, but not the SSF S ei (q), which determines the H contribution to the fourth moment. Furthermore, as it was observed, precisely the latter contribution modifies the highprojectile-velocity asymptotic form of a TCP (polarization) stopping power [29,49].…”

“…(vi) Neither one of the non-MM models considered here satisfies the complete fourth sum rule (68), which includes the electron-ion contribution (25).…”