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Indexed by:期刊论文

Date of Publication:2019-02-01

Journal:RADIATION EFFECTS AND DEFECTS IN SOLIDS

Included Journals:SCIE、EI

Volume:174

Issue:1-2

Page Number:19-30

ISSN No.:1042-0150

Key Words:Plasmon; wake effect; stopping power; image force; 2D materials

Abstract:The interactions of a fast-moving charged particle with two parallel layers, each containing a two-dimensional electron gas (2DEG), which are separated by an insulating material, are investigated by the linearized quantum hydrodynamic model describing plasmon excitations in the 2DEGs. We derive general expressions for the perturbed electron density and the induced potential, as well as the image and stopping forces acting on the charged particle moving parallel to the 2DEGs. The results of our calculations indicate that the value of the dielectric constant of the insulating medium exerts a strong influence on those physical quantities. An asymmetric wake effect appears in both the perturbed electron density and the induced potential, showing a decrease in the amplitude of oscillations and an increase in their wavelength with increasing dielectric constant. A double-peak structure appears in the velocity dependence of the image and stopping forces, which arises due to the plasmon hybridization between the 2DEGs, dependent on the value of the dielectric constant in the insulating medium.