Smith-Purcell Radiation Enhanced By Periodic Split-Ring Resonator Metamaterials

The phenomenon of free electrons crossing the periodic grating surface to stimulate radiation is called Smith-Purcell (SP) effect. The Split-Ring Resonators (SRRs) metamaterials can produce strong resonance in the gap when excited by electromagnetic waves of a certain wavelength. Here, we use the SRRs metamaterials with specific period and slot width to generate the resonance of terahertz frequency band and SP radiation at the same time under the excitation of electron injection. By adjusting relevant parameters, the SP radiation frequency and resonant frequency can be consistent. Through simulation study, it is found that the resonance can greatly enhance the SP radiation. This discovery provides a new idea and method for the development of high power terahertz radiation sources.