Waveguide mode deformation in free-electron lasers

Fajans, J.; Wurtele, J. S.
October 1989
Physics of Fluids B: Plasma Physics;Oct89, Vol. 1 Issue 10, p2073
Academic Journal
The free-electron laser (FEL)-induced modifications to the vacuum waveguide modes are calculated for low-frequency FEL’s. Typically, the mode modifications are large and exhibit complicated axial behaviors. In addition to the wave component with a near vacuum wavenumber, components at two upshifted wavenumbers must be analyzed. Electron beam surface charges and currents are also important. At low gain, effects from all three roots of the FEL dispersion relation must be included. The dominant modification is due to the electron beam space-charge wave.


Related Articles

  • Raman free-electron laser with longitudinal electrostatic wiggler and annular electron beam. Maraghechi, B.; Javan, N. Sepehri // Physics of Plasmas;Sep2001, Vol. 8 Issue 9 

    A linear theory for the parametric instability of a free-electron laser with a longitudinal electrostatic wiggler is presented. A space-charge wave and a predominantly transverse magnetic wave guide mode are excited when a relativistic electron beam is passed through a static spatially periodic...

  • Theory of free-electron laser instability for a relativistic electron beam propagating in a dielectric-loaded waveguide. Choi, Jeong-Sik; Kim, Dong-Eon; Choi, Duk-In; Yang, Soon-Chul; Uhm, Han S. // Physics of Fluids B: Plasma Physics;Jun89, Vol. 1 Issue 6, p1316 

    A free-electron laser (FEL) with a dielectric-loaded waveguide operating in an undulator (multiple mirror) field is analyzed. The stability properties are investigated self-consistently on the basis of the linearized Vlasov–Maxwell equations for an electron distribution function, in which...

  • Competition between two resonance frequency branches in a waveguide free-electron laser. Shu, X. J.; Kawamura, Y.; Tanabe, T.; Li, D. J.; Toyoda, K. // Journal of Applied Physics;1/1/1995, Vol. 77 Issue 1, p426 

    Presents a study that investigated the competition between two resonance frequency branches in a waveguide free-electron laser. Parameters used in the numerical simulations; Effects of slippage on gain; Expression for the steady-state gain in the small-signal low-gain regime.

  • Free-electron laser operation in a sheath helix configuration.. Sharma, Anamika; Chauhan, Ansuya; Tripathi, V.K. // Physics of Plasmas;Jun94, Vol. 1 Issue 6, p2053 

    Reports on a sheath helix loaded waveguide that supports a slow electromagnetic wave which can act as a wiggler for a millimeter-wave free-electron laser (FEL). Sensitivity of the radiation frequency and growth rate as functions of the phase velocity of the pump wave; Tuning of the FEL...

  • Beam space-charge modes in a free-electron laser. Willet, Joseph E.; Aktas, Yildrim; Bolon, Bruce // Physics of Plasmas;Jun96, Vol. 3 Issue 6, p2441 

    Analyzes the propagation of space-charge waves in a Raman free-electron laser. Components of the device under consideration; Development of a solution of the fluid equations and Gauss's law; Derivation of the dispersion relation and the combined effects of the waveguide boundary.

  • Excitation of a transverse magnetic waveguide mode near cutoff in a free-electron laser. Willett, Joseph E.; Aktas, Yildirim; Mehdian, Hassan // Physics of Plasmas;Apr95, Vol. 2 Issue 4, p1311 

    Studies a free-electron laser with a helical wiggler field, axial guide field operating in the collective regime infinitesimally above cutoff of a transverse magnetic mode. Beam-frame analysis of the parametric decay of the wiggler wave into a forward scattered space-charge wave.

  • Helical distributed feedback free-electron laser. Akiba, Tatsuro; Tanaka, Katsuya; Mokuno, Masaaki; Miyamoto, Shuji; Mima, Kunioki; Nakai, Sadao; Kuruma, Shinichiro; Imasaki, Kazuo; Yamanaka, Chiyoe; Fukuda, Masahiko; Ohigashi, Nobuhisa; Tsunawaki, Yoshiaki // Applied Physics Letters;2/5/1990, Vol. 56 Issue 6, p503 

    Results of the implementation of a distributed feedback (DFB) reflector in a free-electron laser (FEL) are described. The reflector was positioned in the interaction region of the FEL waveguide in order to produce narrow bandwidth features in the output spectrum. Both the DFB and wiggler were of...

  • Generation of electromagnetic radiation from a rotating electron ring in a rippled magnetic field. Yin, Y. Z.; Bekefi, G. // Physics of Fluids (00319171);Apr85, Vol. 28 Issue 4, p1186 

    Calculations show that modes resembling the free-electron laser (FEL) instability are excited when electrons move in quasicircular orbits under the combined action of a uniform axial magnetic field and an azimuthally periodic wiggler magnetic field. In.the model, a thin annular ring of rotating...

  • Microwave studies of a tunable free-electron laser in combined axial and wiggler magnetic fields. Fajans, J.; Bekefi, G.; Yin, Y. Z.; Lax, B. // Physics of Fluids (00319171);Jun85, Vol. 28 Issue 6, p1995 

    Measurements of narrow-band (Δω/ω ≤ 0.02) microwave emission from a tunable (7 ≤ ω/2π ≤ 21 GHz) Raman, free-electron laser operating in a single TE[sub 11] waveguide mode are reported. Approximately 100 kW of rf power has been observed at an electronic...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics