Study of a high-order mode terahertz backward wave ocsillator driven by multiple sheet electron beams

The concept of achieving powerful terahertz radiation by the interaction between high-order mode backward wave and multiple sheet electron beams is proposed to increase the operating frequency of the backward wave oscillator (BWO) to a high level such as over 1 THz. For the high-order mode operation, an orthogonal grating waveguide slow wave structure is proposed. Particle-in-cell simulations show that the high-order mode BWO can generate over 0.84 W power in the frequency range of 1.20-1.32 THz. The proposed methodology provides a potential solution to develop compact terahertz radiation sources with high output power and broad tunable bandwidth.