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Title: Development of a Novel High Power Sub-THz Second Harmonic Gyrotron

Journal Article · · Physical Review Letters
 [1]; ; ; ; ; ; ;  [2];  [3]
  1. Tera-Photonics Laboratory, RIKEN, 519-1399, Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-0845 (Japan)
  2. Research Center for Development of Far-Infrared Region, University of Fukui, Fukui 910-8507 (Japan)
  3. Nizhny Novgorod State University, Radiophysical Faculty, Nizhny Novgorod 603600 (Russian Federation)

Record-breaking high power coherent radiation at a subterahertz frequency region from a gyrotron utilizing second harmonic resonance modes was attained with a simple cavity. In order to aim at high power and high frequency simultaneously, the oscillation mode was selected carefully enough to realize stable radiation free from mode competition. The cavity radius was determined from the viewpoints of the oscillation frequency, the coupling coefficient between the electron beam, and the rf-electric field. The cavity length was also optimized for the highest perpendicular efficiency. In addition, a new electron gun which is capable of generating a thin laminar beam for a large current was introduced. Consequently, single mode second harmonic radiation with powers of 52 and 37 kW at frequencies of about 349 and 390 GHz, respectively, was achieved.

OSTI ID:
21370870
Journal Information:
Physical Review Letters, Vol. 103, Issue 22; Other Information: DOI: 10.1103/PhysRevLett.103.225002; (c) 2009 The American Physical Society; ISSN 0031-9007
Country of Publication:
United States
Language:
English