Design of a Sub-THz Extended Interaction Amplifier with Trapezoidal Structure

Due to the superior electromagnetic coupling characteristics, the subwavelength hole array structure has attracted widespread attention. In this paper, a new type of extended interaction amplifier (EIA) is designed by combining the subwavelength hole array structure with the trapezoidal line circuit. The resonant cavity simulation in the $\text{TM}_{31}-2\pi$ mode of terahertz is analyzed. Through the 3D Particle-In-Cell (PIC) simulation, when the input signal is 20-mW, the designed EIA can stably generate 10.25 W power, at 231.4 GHz, with 27.1-dB gain and almost 850 MHz bandwidth.