Initial experimental results of a new triplet harmonic-multiplying gyrotron amplifier (Gyrotriotron)

A new triplet gyrotron amplifier, which we call gyrotriotron, has recently been developed. The device consists of a gyroTWT input stage to modulate the beam at S/sub 1/=1 cyclotron harmonic, a four-unit clustered-cavity as intermediate stage to bunch the beam at S/sub 2/=2 cyclotron harmonic and a gyro-TWT output stage to extract energy from the bunched beam at S/sub 3/=2 cyclotron harmonic. Electronic coupling between neighboring stages is realized through ballistic beam bunching in the radiation-free drift space similar to what happens in a gyroklystron. Because S/sub 3/ = S/sub 2/ = 2S/sub 1/, the device is a harmonic multiplying gyrotron amplifier with a scheme of 1-2-2. The clustered-cavity employed in the gyrotriotron is a group of TE/sub 03/ mode-selected cavities, which are closely adjacent and without any coupling between them.