High Power 340GHz $\mathsf{TM}_{31}$ Mode Extended Interaction Klystron

The design of
$\mathbf{TM}_{\mathbf{31}}$
mode 0.34 THz extended interaction klystron (EIK) with peak power greater than 100W is introduced.
$\mathbf{TM}_{\mathbf{31}}$
mode has a large cavity structure, which can reduce the processing difficulty. The analysis of competition risk from
$\mathbf{Q}_{\mathbf{1}}$
shows that there is no competition risk in the designed structure. The field distribution proves that the designed structure works in
$\mathbf{TM}_{\mathbf{31}}$
mode, and the field increases gradually in each cavity. In the three-dimensional Particle-In-Cell (PIC) simulation, at 337.6GHz, the peak output power of 113.4 W is generated. The corresponding gain, electronic efficiency and 3dB bandwidth are 39.4 dB, 2.17% and 0.32GHz respectively.