Wall-Plug Efficiencies of High-Power Free Electron Lasers Employing Energy Recovery Linacs

Abstract

In a high average power free electron laser (FEL) the wall-plug efficiency is of critical importance in determining the size, complexity and cost of the overall system. The wall-plug efficiency for the FEL oscillator and amplifier (uniform and tapered wiggler) are strongly dependent on the energy recovery process. A theoretical model for electron beam dynamics in the energy recovery linac is derived and applied to the acceleration and de-acceleration of nano-Coulomb electron bunches for a tapered FEL amplifier. For the tapered amplifier, the spent electron beam exiting the wiggler consists of trapped and untrapped electrons. De-accelerating these two populations using different phases of the radio-frequency wave in the recovery process enhances wall-plug efficiency. For the parameters considered here, the wall-plug efficiency for the tapered amplifier can be -40% using this method.

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Document Details

Document Type
Technical Report
Publication Date
Apr 23, 2009
Accession Number
ADA502659

Entities

People

  • Bahman Hafizi
  • Ilan Ben-zvi
  • Joseph R. Peñano
  • Phillip A. Sprangle

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Amplifiers
  • Aspect Ratio
  • Dynamics
  • Electron Beams
  • Electron Energy
  • Electrons
  • Free Electron Lasers
  • Free Electrons
  • Frequency
  • Lasers
  • Magnetic Fields
  • Military Research
  • Oscillators
  • Physics
  • Radiation
  • Radio Frequency
  • Space Charge

Fields of Study

  • Physics

Readers

  • Electronics Engineering
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Microelectronics