Studies on novel terahertz electronic sources based on doubly-corrugated metasurfaces

In this paper, a novel terahertz electronic sources based on the interaction between spoof surface plasmons (SSP) and injected electron beam on the doubly-corrugated metasurfaces are studied by particle-in-cell (PIC) simulation. The SSP fields, dispersion and modes on the two identical corrugated surfaces are calculated and then presented theoretically and numerically. Besides, the influence of the separated distance between these two corrugated metal surfaces on different SSP dispersion modes is specifically analyzed. The PIC simulation results show that the output power increases along with the decreased gap distance at the frequency near 1THz for the given variation range. The maximum output power can reach above 1.5W by the same 19.55kV, 1A half duty-cycle electron beam by decreasing gap size from 110μm to 70μm. The obtained SSP power can be increased by decreasing gap size further. The investigations on the excitation and amplification of SSP on the doubly-corrugated metasurfaces will open new venues for the development of electronic sources from microwave to THz regime.