Ab Initio Evaluation of Plasmon Lifetimes in the Alkali Metals

Wei Ku; Adolfo G. Eguiluz

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arXiv · cond-mat/9809054

Ab Initio Evaluation of Plasmon Lifetimes in the Alkali Metals

Wei Ku·Adolfo G. Eguiluz

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Abstract

The anomalous plasmon linewidth dispersion (PLD) measured in K by vom Felde, Sprosser-Prou, and Fink (Phys. Rev. B 40, 10181 (1989)), has been attributed to strong dynamical electron-electron correlations. On the basis of ab initio response calculations, and detailed comparison with experiment, we show that the PLD of K is, in fact, dominated by decay into particle-hole excitations involving empty states of d-symmetry. For Li, we shed new light on the physics of the PLD. Our all-electron results illustrate the importance of ab initio methods for the study of electronic excitations.

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Wei Ku, Adolfo G. Eguiluz. 1998-09-02. Ab Initio Evaluation of Plasmon Lifetimes in the Alkali Metals. https://arxiv.org/abs/cond-mat/9809054

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