Mechanisms for the production of harmonics in free electron lasers
نویسندگان
چکیده
Harmonics m the radiation of a free electron laser are useful for extending the range of tuning, may originate in spontaneous or parametric processes, and can take part m stimulated emission or amplification . These mechanisms exhibit interesting analogies with those of nonlinear optics . Apart from the well known nonparametric gam analogous to stimulated Brilloum scattering, they include third-harmonic generation and other four-wave mixing parametric processes, with spatial harmonics of the electron density taking the place of the higher-order terms in the nonlinear dielectric susceptibility . We investigate these mechanisms using a one-dimensional model.
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