Free Electron Laser Short Pulse Simulation and Two-Mode Sideband Analysis
Abstract
The Stanford Free Electron Laser (FEL), like many FELs is driven by extremely short electron pulses which drive equally short optical pulses. Simulations of the Stanford FEL describe the trapped-particle instability leading to sideband frequencies and limit-cycle behavior. Comparisons are made of recent experimental results that show close agreement between the desynchronism curves, optical spectra, and the electron spectra. The second part of this thesis analyzes sideband behavior when two modes are present in an FEL oscillator. Using two-mode wave and pendulum equations derived from Maxwell's and the Lorentz force equations, the gain and phase shift for each initial phase of the two-mode optical field can be determined numerically. Averaging over all initial phases determines the FEL optical performance. In steady-state the presence of the sideband effectively reduces the undulator's length, delaying the onset of saturation. This allows more power to be generated in the optical field then possible with only a single mode. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1991
- Accession Number
- ADA246044
Entities
People
- Gregory A. Cord
Organizations
- Naval Postgraduate School