Stimulated Smith–Purcell radiation

The design of free-electron lasers (FELs) based on submillimeter-range undulators involves difficulties associated with the fabrication of undulators with a very small period. To do this also requires accelerators with high-energy electron beams (>50 MeV). It should also be taken into account that these facilities use precision and expensive magnetic systems. In some works, an alternative FEL mechanism based on the use of the Smith–Purcell radiation (SPR) was considered. To realize the feedback in such an FEL, one must use a basically different cavity scheme. This work reports the results of experimental study on the stimulated SPR in a “transverse” cavity.