High purity mode operation of a gyrotron


I. Ogawa T. Idehara1, S.Maeda, R. Pavlichenko1, S.Mitsudo1, D.Wagner2

and M.Thumm3

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.


Als Vortrag:

26th Int. Conf. on Infrared and Millimeter Waves, Toulouse, Sept. 10-14, 2001