IFEL acceleration in a helical undulator
What the animation shows
The three-dimensional trajectory follows an electron through a helical undulator. The energy plot rises from 1.20 to 2.97 MeV. The accompanying taper plot shows how the undulator pitch and magnetic field vary along the interaction region.
Keeping the electron in phase
The inverse free-electron laser (IFEL) mechanism transfers energy from an electromagnetic wave to the electron's transverse motion. As the electron accelerates, a gradual change in the undulator period and field maintains the resonance condition. The model integrates the full relativistic Lorentz-force equation in COMSOL Multiphysics.