Plasma waves in a two-dimensional graphene-based superlattice

In this paper, the dependence of the plasma wave frequency on the wave vector and the density of plasma excitations in the electron gas of a two-dimensional graphene superlattice are theoretically investigated. The calculations are performed based on the quantum theory of plasma waves in the random phase approximation taking into account the umklapp processes. The plasmon frequency estimate for the currently theoretically studied superlattices based on graphene on a striped substrate yields ω ∼ 10$^13$ c$^−1$. A comparison of the plasmon dispersion laws of graphene and quantum semiconductor superlattices is performed.