Free electron laser in a stripline geometry

Abstract

A thin dielectric slab over a conducting sheet is presented as a low-loss slow-wave guiding system. When one introduces a magnetic wiggler into the system one may efficiently excite millimeter waves by passing a sheet electron beam just above the dielectric surface. For realistic parameters, the energy requirements on the beam are greatly reduced due to the wiggler. The frequency ω₁ and the growth rate G are very sensitive to beam energy. G scales as I_b^⅓B^⅔ with beam current I_b and wiggler strength B₀, and decreases with increasing width of the dielectric and increasing ω₁.