Cherenkov free-electron laser with a planer dielectric waveguide

The dispersion relations of a planar dielectric waveguide used in Cherenkov free-electron lasers are derived out and the existence of a group of odd modes which can be simultaneously excited with the previously considered even modes is reported. Discussion on the dependence of the radiation frequency and single-pass gain on the system parameters, the dielectric thickness, the beam energy and the beam channel width, is presented and the effects of the odd modes on the Cherenkov free-electron laser operation are investigated