Output System for a 170-GHz/1.5-MW Continuous Wave Gyrotron Operating in the TE28,12 Mode

In this paper, design aspects of the output system of a 170-GHz/1.5-MW continuous wave gyrotron operating in the TE_28,12 mode is presented for testing the latest version of gyrotron design suite (GDS.V3.2014), which has been equipped with new features. The output system has been incorporated and showcased here considering the design aspects of the output system of this specific gyrotron as a case study. A nonlinear up-taper has been designed using a multiobject particle swarm evolutionary algorithm and the design of an advanced dimpled-wall launcher is carried out using launcher optimization tool. Single-disk chemical vapor deposition (CVD) diamond and CVD boron nitride windows have been designed to take out the output power. Besides, the reconstruction of the wave phase at different planes outside the tube is calculated by an iterative phase retrieval algorithm. The Gaussian mode content achieved by the launching system is 99.5%. In addition, design of a matching optics unit has also been done considering a very recent approach for off-axis incident beams.