Powerful radiation source at 0.35 THz based on overmoded, periodic cavities

We present the design of a cylindrical, two-dimensional periodic surface lattice structure intended for use as the interaction region of an electron beam driven, pulsed Cherenkov source. We demonstrate production of high peak power radiation output at 0.35 THz. The interaction region is oversized and mode selection is achieved by the coupling of volume and surface fields to form a coupled cavity eigenmode. The work is also applicable to different frequencies, and the diameter of the cavity can be increased to achieve higher output powers.