[Table of Contents]

Plasma and Fusion Research

Volume 2, 024 (2007)

Rapid Communications

Observation of Simultaneous Oscillation of Multiple Modes in a CW 300 GHz Gyrotron
Teruo SAITO, Tomoaki NAKANO, Seitaro MITSUDO, Isamu OGAWA and Toshitaka IDEHARA
Research Center for Development of Far-Infrared Region, University of Fukui
(Received 17 April 2007 / Accepted 2 May 2007 / Published 11 June 2007)

Abstract

Multi-mode oscillation was observed in a 300 GHz fully CW gyrotron. It has been developed and installed in the Research Center for Development of Far-Infrared Region, University of Fukui as a power source of a submillimeter-wave material processing system. This gyrotron delivers 1.75 kW/CW at maximum. The radiation pattern is a Gaussian beam when the magnetic field strength Bc at the cavity is properly adjusted. However, within a range of Bc values, simultaneous oscillation of competing modes is observed, manifesting in radiation of the output power in multiple directions.

Keywords

submillimeter CW gyrotron, radiation pattern, Gaussian beam, multi mode oscillation, material processing

DOI: 10.1585/pfr.2.024

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References

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This paper may be cited as follows:

Teruo SAITO, Tomoaki NAKANO, Seitaro MITSUDO, Isamu OGAWA and Toshitaka IDEHARA, Plasma Fusion Res. 2, 024 (2007).