Experimental Operation of a Cyclotron Autoresonance Maser Oscillator at the Second Harmonic

Abstract

Experimental results are presented of the first cyclotron autoresonance maser oscillator operated using the second harmonic of the cyclotron frequency. An interaction efficiency of 3.9% has been measured at a frequency of 14.27 GHz, using an 80 ns pulsed, 14 A electron beam of energy 300 keV, to produce a coherent microwave power of 170 kW. Emission occurred at 3.7 times the relativistic cyclotron frequency, due to the large Doppler frequency increase and second harmonic interaction.