Coherent Terahertz Smith-Purcell radiation from a two-section model

This paper presents a two-section model to produce beam bunching and obtain coherent Terahertz (THz) Smith-Purcell (SP) radiation. Based on the mechanism of the Cherenkov oscillator, a continuous beam is bunched in the first section without external signal. In the second section, the coherent THz-SP radiation is stimulated by the bunched beam interacting with open grating. The Particle-In-Cell (PIC) simulations show that the beam is effectively bunched and the strongest radiation is observed at 51° with the frequency of 194 GHz in this scheme.