Two-Beam Free-Electron Lasers and Self-Injected Nonlinear Harmonic Generation

Studies of Harmonic Generation in Free Electron Lasers

The Effect of Wiggler Imperfections on Nonlinear Harmonic Generation in Free-Electron Lasers

The generation of harmonics through a nonlinear mechanism driven by bunching at the fundamental has sparked interest in using this process as a path toward an X-ray free-electron laser (FEL). An important issue in this regard is the sensitivity of the nonlinear harmonic generation to wiggler imperfections. Typically, linear instabilities in FELs are characterized by increasing sensitivity to bo...

Nonlinear wave propagation in free-electron lasers.

Nonlinear Simulation of Harmonically Coupled Two-Beam Free-Electron Laser

A nonlinear model of two-beam free-electron laser (FEL) in the absence of slippage is presented. The two beams are assumed to be cold with different energies and the fundamental resonance of the higher energy beam is at the third harmonic of lower energy beam. By using Maxwell’s equations and full Lorentz force equations of motion for the electron beams, coupled differential equations are deriv...

Limitations of Electron Beam Conditioning for Free-Electron Lasers

Several ideas have been proposed to ‘condition’ an electron beam prior to the undulator of a Free-Electron Laser (FEL) by increasing each particle’s energy in proportion to the square of its transverse betatron amplitude. This conditioning enhances FEL gain by reducing the axial velocity spread within the electron bunch. We demonstrate that for symplectic beamlines, and independent of the metho...