Simulations of a W-Band Circular TWT

We are exploring the amplification of W-band electromagnetic radiation using a dielectric-loaded traveling wave tube (TWT) by employing several particle-in-cell (PIC) codes. We are seeking to replicate recent results obtained by a Naval Research Laboratory's (NRL's) dielectric-loaded TWT design [1] consisting of a solid circular electron beam (26 kV, 100 mA and 0.185 mm beam radius) surrounded with dielectric material, ε
_r
=13.5, and coupled to a TM01 electromagnetic wave at a frequency of 94 GHz. NRL used a finite-difference-timedomain (FDTD) formulation in a 2-D cylindrical coordinate system to perform the dielectric-loaded TWT simulations. In our work, we have opted for PIC simulations comparing three different software tools-a 3-D Cartesian coordinate system `FDTD-PIC method-based MAGIC', `CST Electromagnetic and Multiphysics Simulation Studio Suite', and `Improved Concurrent Electromagnetic Particle-In-Cell (ICEPIC)'. This paper summarizes our results from these studies.