title: High-gain wide-band gyrotron traveling wave amplifier with a helically corrugated waveguide
abstract: First bandwidth measurements of a novel gyrotron amplifier are presented. The coupling between the second harmonic cyclotron mode of a gyrating electron beam and the radiation field occurred in the region of near infinite phase velocity over a broad bandwidth by using a cylindrical waveguide with a helical corrugation on its internal surface. With a beam energy of 185 keV, the amplifier achieved a maximum output power of 1.1 MW, saturated gain of 37 dB, linear gain of 47 dB, saturated bandwidth of 8.4 to 10.4 GHz ( 21% relative bandwidth), and an efficiency of 29%, in good agreement with theory.
authors.affiliation: Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, 603600, Russia.
authors.initials: VL
authors.lastname: Bratman
authors.initials: AW
authors.lastname: Cross
authors.initials: GG
authors.lastname: Denisov
authors.initials: W
authors.lastname: He
authors.initials: AD
authors.lastname: Phelps
authors.initials: K
authors.lastname: Ronald
authors.initials: SV
authors.lastname: Samsonov
authors.initials: CG
authors.lastname: Whyte
authors.initials: AR
authors.lastname: Young