Analysis of Thermal Loss in the THz Sheet Beam Folded Waveguide TWT

The sheet beam (SB) tunnel was introduced in the terahertz (THz) folded waveguide (FW) traveling wave tube (TWT) for power enhancement. In this paper, the thermal loss in the SB FW-TWT operating at 220GHz was studied with the help of Particle-in-cell (PIC) simulation. The amplification performance of the SB-TWTs constructed with lossy metal and PEC was compared. The main influencing factors on the thermal loss, including particle collision loss and ohmic loss, in the SB FW-TWT were observed and analyzed. The results give a closer look into the energy transfer process and technical assistance in parameter optimization.