Wednesday, May 29, 2013

High Power Wideband Gyrotron Backward Wave Oscillator Operating towards the Terahertz Region


He, W., et al., High Power Wideband Gyrotron Backward Wave Oscillator Operating towards the Terahertz Region. Phys. Rev. Lett., 2013. 110(16): p. 165101.


Experimental results are presented of the first successful gyrotron backward wave oscillator (gyro-BWO) with continuous frequency tuning near the low-terahertz region. A helically corrugated interaction region was used to allow efficient interaction over a wide frequency band at the second harmonic of the electron cyclotron frequency without parasitic output. The gyro-BWO generated a maximum output power of 12 kW when driven by a 40 kV, 1.5 A, annular-shaped large-orbit electron beam and achieved a frequency tuning band of 88-102.5 GHz by adjusting the cavity magnetic field. The performance of the gyro-BWO is consistent with 3D particle-in-cell numerical simulations.