High-repetition-rate ultra-broadband coherent diffraction radiation THz source

We proposed a coherent diffraction radiation (CDR) THz source with megahertz repetition rate, which is based on ultra-short electron beams of the free electron laser THz (FEL-THz) facility at CAEP. With theoretical analysis, numerical calculation and particle-in-cell (PIC) simulation, the pulse duration of this THz source is proved to be several picoseconds. The center frequency is tunable from 100 GHz to 400 GHz and the cut-off frequency is from 1 THz to 2 THz. The peak power is in 10 kW region and the average power can be a few watts. Furthermore, the THz power is proportional to the square of the electron beam current.