Nonlinear mixing of lasers and terahertz generation on CNT embedded metal surface

A scheme of terahertz generation, employing carbon nanotubes (CNTs) embedded metal surface is proposed. The surface is irradiated by two laser beams at angle of incidence θ. The lasers exert a ponderomotive force on CNT electrons at the beat frequency ω=ω1-ω2 and produce a nonlinear current, turning the nanotubes into an array of antennae emitting beat frequency THz radiation. The THz field is resonantly enhanced at the plasmon resonance, ω = ω p β / 2 , where ωp is the plasma frequency of the CNT electrons and β is a parameter that characterizes the metallic susceptibility of the CNTs. The collisions are a limiting factor and cause heating of CNTs.