Phase trapping efficiency enhancement for cyclotron amplifiers

Summary form only given. Cyclotron masers1 are fast wave devices which typically operate in the centimetre to submillimetre region of the electromagnetic spectrum. They find application in numerous fields such as radar, plasma science and materials processing. Two amplifer devices have been studied to establish their potential for efficiency enhancement. By tapering either the magnetic field or the physical dimensions of each device in their respective interaction regions electron-wave synchronism is maintained despite the increase in gyro-frequency resulting from decreasing beam energy.