Frequency modulated free electron laser

L. T. Campbell, B. W. J. McNeil

Research output: Contribution to journalLetterpeer-review

1 Citation (Scopus)
18 Downloads (Pure)


It is shown that the output frequency of a free electron laser may be modulated to generate a series of modes that span a bandwidth of at least an order of magnitude greater than the normal FEL bandwidth. This new method of frequency modulated FEL operation has close analogies to frequency modulation in conventional cavity lasers. The FM-FEL is analysed and described in the linear regime by a summation over the exponentially amplified frequency modes.
Simulations using a 3D, broad bandwidth, numerical code also demonstrate FM-FEL operation for parameters typical of FEL facilities currently under construction. Harmonic bunching methods are used to seed the FM-FEL modes to generate a temporally correlated frequency modulated output over a large bandwidth. This new, FM-FEL mode of operation scales well for X-ray generation, offering users a significantly new form of high-power, short wavelength FEL output.
Original languageEnglish
Pages (from-to)8792-8799
Number of pages8
JournalOptics Express
Issue number6
Publication statusPublished - 18 Mar 2019


  • electric fields
  • free electron lasers
  • frequency modulated lasers


Dive into the research topics of 'Frequency modulated free electron laser'. Together they form a unique fingerprint.

Cite this