The effect of plasma on metal grating free electron laser

The dispersion relation of a metal grating free electron laser is studied to include the effect of plasma filling. The introduction of plasma into the device reduces the axial electric field at the grating surface and peaks at the plasma region. It is observed that, depending on the plasma density and beam-grating waveguide operating parameters, substantial enhanced growth of the instability can be obtained with higher emission frequency than that of the standard metal grating free electron laser.<
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