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arXiv · 2009.08098

Effect of Dynamic Ions on Band Structure of Plasmon Excitations

Abstract

In this paper we develop a new method to study the plasmon energy band structure in multispecies plasmas. Using this method, we investigate plasmon dispersion band structure of different plasma systems with arbitrary degenerate electron fluid. The linearized Schr\"{o}dinger-Poisson model is used to derive appropriate coupled pseudoforce system from which the energy dispersion structure is calculated. It is shown that the introduction of ion mobility, beyond the jellium (static ion) model with a wide plasmon energy band gap, can fundamentally modify the plasmon dispersion character leading to a new form of low-level energy band, due to the electron-ion band structure mixing. The effects ionic of charge state and chemical potential of the electron fluid on the plasmonic band structure indicate many new features and reveal the fundamental role played by ions in the phonon assisted plasmon excitations in the electron-ion plasma system. Moreover, our study reveals that ion charge screening has a significant impact on the plasmon excitations in ion containing plasmas. The energy band structure of pair plasmas confirm the unique role of ions on the plasmon excitations in many all plasma environments. Current research helps to better understand the underlying mechanisms of collective excitations in charged environment and the important role of heavy species on the elementary plasmon quasiparticles. The method developed in this research may also be extended for complex multispecies and magnetized quantum plasmas as well as to investigation the surface plasmon-polariton interactions in nanometallic structures.

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BibTeXRIS

M. Akbari-Moghanjoughi. 2020-09-17. Effect of Dynamic Ions on Band Structure of Plasmon Excitations. https://doi.org/10.1063/5.0026298

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