Research on a Highly Overmoded Slow Wave Circuit for 0.3-THz Extended Interaction Oscillator

Here, we present the complete design process of a highly overmoded slow wave circuit (SWC) stably operating in the quasi-TM04 mode for terahertz (THz) extended interaction oscillator (EIO). The developed interaction circuit emits THz frequency electromagnetic radiation through structural size of the engineered millimeter-wave (MMW) circuits, which provides a new technological horizon for overcoming the engineering challenges caused by the limitation of circuit size. Through careful engineering of the electron optical system, a cylindrical beam with a diameter of 0.38 mm and a current of 0.25 A is obtained at a bias of 14.8 kV. Through the particle-in-cell (PIC) simulation, these new design approaches have been shown to achieve an output power of 250 W at 0.3 THz in a cylindrical cavity with an inner diameter of 4.16 mm.