Terahertz generation via laser coupling to anharmonic carbon nanotube array

A scheme of terahertz radiation generation employing a matrix of anharmonic carbon nanotubes (CNTs) embedded in silica is proposed. The matrix is irradiated by two collinear laser beams that induce large excursions on CNT electrons and exert a nonlinear force at the beat frequency ω = ω1−ω2. The force derives a nonlinear current producing THz radiation. The THz field is resonantly enhanced at the plasmon resource, ω = ω p ( 1 + β ) / 2, where ωp is the plasma frequency and β is a characteristic parameter. Collisions are a limiting factor, suppressing the plasmon resonance. For typical values of plasma parameters, we obtain power conversion efficiency of the order of 10−6.