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arXiv · 1601.01373

Plasmon Excitations for Encapsulated Graphene

Godfrey Gumbs·Norman J. M. Horing·Andrii Iurov·Dipendra Dahal
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Abstract

We have developed an analytical formulation to calculate the plasmon dispersion relation for a two-dimensional layer which is encapsulated within a narrow spatial gap between two bulk half-space plasmas. This is based on a solution of the inverse dielectric function integral equation within the random-phase approximation (RPA). We take into account the nonlocality of the plasmon dispersion relation for both gapped and gapless graphene as the sandwiched two-dimensional (2D) semiconductor plasma. The associated nonlocal graphene plasmon spectrum coupled to the "sandwich" system is exhibited in density plots, which show a linear mode and a pair of depolarization modes shifted from the bulk plasma frequency.

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Godfrey Gumbs, Norman J. M. Horing, Andrii Iurov, Dipendra Dahal. 2016-01-07. Plasmon Excitations for Encapsulated Graphene. https://doi.org/10.1088/0022-3727/49/22/225101

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