A new free electron laser interaction mechanism based on a quasi-periodic wiggler

Summary form only given. It is known that free electron lasers (FELs) based on a straightforward wiggler of single periodicity induce a sinusoidal density modulation on the electron beam employed. In the visible portion of the spectrum, a sinusoidally modulated electron beam radiates at one wavelength as well as its harmonics. Beam-wave interaction in such a conventional FEL configuration is relatively well understood. In order to arrive at an improved FEL performance however, it is of considerable interest to explore unconventional interaction mechanisms. In this contribution, we consider a new free electron laser configuration based on a quasiperiodic wiggler magnet having two different wiggler periods.