ABSTRACT
This chapter presents a general consideration which is based on the Kubo formula and takes into account both the scattering due to finite-range disorder and a long-range partly screened variation of concentration. It also presents the basic equations which describe the inter- and intraband mechanisms of absorption and consider partly screened long-range disorder in gated graphene. The chapter analyzes the spectra of relative absorption and their dependencies on the temperature disorder and as well as on the doping conditions. The absorption of heavily doped graphene in the terahertz and midinfrared spectral regions is considered taking into account both the elastic scattering due to finite-range disorder and the variations of concentration due to long-range disorder. The gate voltage and temperature dependencies of the absorption efficiency are calculated. It is demonstrated that for typical parameters, the smearing of the interband absorption edge is determined by a partly screened contribution to long-range disorder while the intraband absorption is determined by finite-range scattering.
