High purity mode operation of a gyrotron
I. Ogawa T. Idehara1, S.Maeda, R. Pavlichenko1, S.Mitsudo1, D.Wagner2
Faculty of Engineering, Fukui University, Fukui 910-8507, Japan
1Research Center for Development of Far-Infrared Region, Fukui University,
Fukui 910-8507, Japan
2Institut für Plasmaforschung, Universität Stuttgart,
Pfaffenwaldring 31, D-70569 Stuttgart, Germany
3Forschungszentrum Karlsruhe, Institut für Hochleistungsimpuls- und Mikrowellentechnik, P.O. Box 3640, D-76021 Karlsruhe, Germany
High frequency gyrotrons are characterized by their capacity to deliver high powers and their frequency step-tunability due to the alternation of the operating mode. Very often the gyrotron output needs to be converted into a Gaussian-like beam because the gyrotron generates radiation with TEmn mode structure. High output mode purity is necessary for an effective conversion.
In order to improve mode purity, a nonlinear cavity which was designed using a scattering matrix code and exquisitely fabricated is installed in the Gyrotron FU VA. Now the final preparation for operation in high purity mode regime is in progress.
26th Int. Conf. on Infrared and Millimeter Waves, Toulouse, Sept. 10-14, 2001