Echo-enabled tunable terahertz radiation generation with a laser-modulated relativistic electron beam

Zhen Wang, Dazhang Huang, Qiang Gu, Zhentang Zhao, Dao Xiang
2014 Physical Review Special Topics. Accelerators and Beams  
A new scheme to generate narrow-band tunable Terahertz (THz) radiation using a variant of the echo-enabled harmonic generation is analyzed. We show that by using an energy chirped beam, THz density modulation in the beam phase space can be produced with two lasers having the same wavelength. This removes the need for an optical parametric amplifier system to provide a wavelengthtunable laser to vary the central frequency of the THz radiation. The practical feasibility and applications of this
more » ... heme is demonstrated numerically with a start-to-end simulation using the beam parameters at Shanghai Deep Ultraviolet Free-Electron Laser facility (SDUV). The central frequency of the density modulation can be continuously tuned by either varying the chirp of the beam or the momentum compactions of the chicanes. The influence of nonlinear RF chirp and longitudinal space charge effect have also been studied in our article. We also briefly discuss how one may retrieve the beam longitudinal phase space through measurement of the THz density modulation.
doi:10.1103/physrevstab.17.090701 fatcat:nmrmkb7yeveoregk7melomrkci