Three dimensional nonlinear theory of the free electron laser (FEL)

This paper presents a self-consistent nonlinear treatment of 3-D effects associated with (i) the electron beam and (ii) the radiation beam in a steady state free electron laser (FED amplifying configuration. Our formulation also incorporates various efficiency enhancement schemes. We find that the 3-D effects can lead to substantial differences in the results compared to the 1-D theory. Finally a 3-D numerical illustration of a 10.6 μm FEL is given.