Higher harmonics generation during the propagation of ultra-short optical pulse in a medium of carbon nano-tubes with nonlinear absorption

The problem of the propagation of an extremely short optical pulse in a medium of carbon nanotubes with nonlinear absorption and amplification is considered. Nonlinear absorption is described phenomenologically based on published data. The mode in which the gain is higher than the linear absorption coefficient is considered. This mode is also described phenomenologically. The extremely short optical pulse is considered on the basis of Maxwell's equations, with a microscopically calculated dependence of the current on the pulse field. The possibility of efficient generation of higher harmonics that are not initially present in the pulse is shown.