Simulation of Smith-Purcell radiation from compact terahertz source

The characteristics of stimulated Smith-Purcell radiation in THz region are simulated and numerically calculated. The experimental device is designed to be compact. The notion of the design for the experiment device is originated from the prototype of the Shanghai Electron Beam Ion Trap. Strong axial magnetic field is necessary to achieve high current and low emittance of electron beam. The simulation results of dynamic characteristics for the electron beam show that an average beam current can be as high as 0.2 A with an RMS beam radius of 75 μm, which is the precondition to work as free electron laser(FEL) while passing over the grating surface. Based on the theory of Andrews and Brau, we have optimized the parameters of grating to ensure the emission angle is near 60°. And the calcula