Transitions between non-convex to hyperbolic plasmonic regions in the Beryllene-Graphene-Beryllene trilayer structure

Abstract

Meta-materials are an important class of materials in condensed matter physics which have unusual optical properties. They can be used to regulate light and wave propagation, in which natural hyperbolic and non-convex plasmons are characteristics that can be observed. In this paper, we study the optical properties of the Beryllene-Graphene-Beryllene (BeCBe) hetero-trilayer and show that this material has hyperbolic plasmons in the THz frequency region and non-convex plasmons. We find that most of the plasmon energy propagation along the qy axis for the hyperbolic region, and that there is elliptic character at 1029.71 THz. The starting point of the hyperbolic region occurs at a frequency of 289.31 THz, which is the first and the narrowest hyperbolic window. Due to the existence of a high density of free electrons in the BeCBe plasmonic material, the presence of the visible region in the third hyperbolic window causes a high plasma frequency.