Generation of terahertz radiation through nonlinear Thomson scattering by two moderate-intensity laser fields

Abstract

A new scheme for the generation of the terahertz (THz) radiation based on the nonlinear Thomson scattering is proposed through two moderate-intensity laser fields. It is found that the THz radiation can be generated in the nonlinear Thomson backscattering spectrum by two moderate-intensity plane wave laser fields with no need of a strong external magnetic field. In this scheme, the amplitude threshold required to generate the THz radiation for two laser fields can be significantly reduced, and the amplitude threshold can even be less than half that of the case of using only a single laser field. It is also shown that in the two moderate-intensity laser fields, the intensity of the THz radiation can also be effectively improved and optimized by increasing the amplitude ratio and reducing the frequency ratio of the two laser fields, and extending the period of the electron motion via the control of the frequency ratio.