LAUSR

The generation of Terahertz (THz) radiation by a density modulated relativistic electron beam (REB) using rippled density plasma, oriented at a suitable angle along the direction of radiation wave, is being investigated in this paper. The non-linear interaction of density modulated REB with ripple density plasma modifies the dispersion relation of the radiation wave co-propagating with the beam wave. Using fluid equations model, it is found that the requisite ripple wavelength decreases as the ripple angle increases and becomes steeper for resonant THz radiation emission. Thus, the radiation wavelength in terahertz range can be tuned by varying the ripple wavelength and beam energy. In addition, it is investigated that the growth rate of THz radiation emission scales as the one-third power of beam current, two-third power of ripple plasma density, and one-third power of modulation index. The output power and efficiency of THz radiation emission depend on the modulation index and reach the largest value wh...