Three-dimensional nonlinear analysis of an E×B drifting electron laser

In this paper we numerically investigate the nonlinear evolution of the E × B drifting electron laser (DEL) [1, 2] for an amplifier configuration in which an electron beam propagates through a periodic magnetic field (wiggler) and undergoes a relativistic E × B drift in orthogonal static electric and magnetic fields. A set of coupled nonlinear differential equations is given in three dimensions which controls the self-consistent evolution of TE modes in a rectangular waveguide as well as the trajectories of an ensemble of electrons. Our numerical simulations are conducted to model a 35 GHz amplifier with an electron beam energy of 3.5 MeV. The results show that the radiation energy in the DEL mainly comes from the change in the kinetic energy of the electron beam, and the DEL, compared with the free-electron laser (FEL) with similar operating parameters, has higher interaction efficiency and peak power.