Abstract

The phenomenon of harmonic generation can lead to extension of the tunable range of FEL to higher frequencies without using ever higher electron beam energies.¹ Linearly polarized wigglers have been utilised for this purpose. An analysis of the electron beam dynamics in such a configuration shows that the harmonics are generated due to the resulting axial electron oscillations of small amplitude. Following single particle approach, we show here that similar electron dynamics can be generated by using circularly polarized wigglers alongwith an appropriately directed axial magnetic field of suitable strength.

© 1990 Optical Society of America