Generation and amplification of terahertz radiation in carbon nanotubes

Abstract

The Boltzmann kinetic equation was used to investigate and derived theoretically the current density characteristics of carbon nanotubes exposed simultaneously to both constant (dc) and high-frequency (ac) electromagnetic fields. Generation and amplification of terahertz radiation at room temperature was predicted. We demonstrated that this can suppress electric current instabilities while still preserving a broadband THz gain. We have further shown that THz gain in the conditions of suppressed electric instabilities can be possible for direct current generation in carbon nanotubes by mixing two coherent electromagnetic waves with commensurate frequencies.