Double-Corrugated Waveguide Slow Wave Structure With Grating for THz Backward Wave Oscillator

This article proposes a novel double-corrugated waveguide with grating (DCWG) slow wave structure (SWS) for the development of a broadband high-power terahertz (THz) back-wave oscillator (BWO). By analyzing the electromagnetic properties, it is found that this SWS is suitable for interaction with a circular electron beam, with high interaction impedance and large “cold” bandwidth. In addition, particle-in-cell (PIC) simulation results indicate that the BWO based on the DCWG SWS can generate an output power exceeding 39.5 W in the frequency range of 327.4–362.2 GHz when the electron beam voltage is between 17 and 26 kV. In particular, at a voltage of 19.5 kV, the output power of the BWO can reach 52 W at a typical operating frequency of 0.34 THz. Therefore, this device has significant potential as a broadband, high-power THz radiation source.