Terahertz radiation generation process in the medium based on the array of the noninteracting nanotubes

Abstract

Consideration of periodically alternating arrays of noninteracting carbon nanotubes with the metal type of conductivity as elements of the quantum layer heterostructures (quantum wells), which will play the role of the active field, is suggested. From the earlier obtained results based on the models of the elementary cell, it follows that the system in the neighborhood of the Dirac points at the presence of the longitudinal electric field will have equidistant spectrum. The eigenvalues of the energies do not depending on the longitudinal electric field. The two-component eigenfunctions do not depend on the longitudinal electric field. The amplification of the generation terahertz radiation by the analogy with the cascade lasers in the multilevel medium, based on the system of the noninteracting metallic carbon, is considered. If concentration of the nanotubes is 107 cm−2 then the output power per unit area will be about \(Q \sim n_{0} k_{0} \hbar \omega J_{k} /e \approx 8\;{\text {W}}/{\text {cm}}^{2}\). The wavelength of the terahertz radiation is 65 µm.