• W. Liu, W.-H. Huang, C.-X. Tang, D. Wu
  TUB, Beijing

The THz wave has some unique characteristics resulting in varieties of applications to medical and industrial imaging, biomedical research and material science,etc. The various schemes for generating the THz waves have been employed. At the present time, an intense interest has been raised in the Smith-Purcell devices, for which is a promising alternative in development of a tunable, compact, powerful of THz radiation source. In this paper, the radiation characteristics of terahertz (THz) Smith-Purcell radiation generated from the ultrashort electron beam are analyzed with the help of three-dimensional particle-in-cell simulation, the radiation power and energy are obtained the PIC simulation. The radiation characteristics generated from train bunches are compared with that of single bunch. The formation factors including the longitudinal and transverse are calculated. Through this study, we observe that the radiation power is enhanced and the band width can be adjusted with the train bunches.