The electromagnetic response of graphene and the spectrum of collective plasmon
excitations are studied as a function of wave vector and frequency. Our calculation is based
on the tight-binding band structure, including both valleys. As a result, near the Dirac points
we find plasmons whose dispersion is similar to that obtained in the single-valley
approximation by Dirac fermions with some anisotropy though. In contrast to the calculation
for a single Dirac cone, we find a stronger damping of the plasmon modes due to interband …

We introduce a method for calculating the dielectric function of nanostructures with an
arbitrary band dispersion and Bloch wave functions. The linear response of a dissipative
electronic system to an external electromagnetic field is calculated by a self-consistent-field
approach within a Markovian master-equation formalism (SCF-MMEF) coupled with full-
wave electromagnetic equations. The SCF-MMEF accurately accounts for several
concurrent scattering mechanisms. The method captures interband electron-hole-pair …