[Table of Contents]

Plasma and Fusion Research

Volume 8, 2401085 (2013)

Regular Articles


Higher Order Mode Radiations of Weakly Relativistic Oversized Backward Wave Oscillator
Kazuo OGURA, Kiyoyuki YAMBE, Shinji HASEGAWA, Takayuki IWASAKI, Kazumasa YAMAMOTO and Yoshihiro KOBARI
Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan
(Received 22 November 2012 / Accepted 22 April 2013 / Published 19 June 2013)

Abstract

Higher order mode radiations of oversized K-band backward wave oscillator (BWO) are examined experimentally. By injecting an annular beam in the weakly relativistic region less than 100 kV, a beam mode with harmonic number n = 1 excites BWO radiations based on the TM01 surface wave. The same beam mode excites higher order modes leading to radiations in the U- and E-bands. The power levels of the higher order modes are hundreds of times smaller than that of BWO due to the surface wave. For a beam mode with n = 2, higher order mode radiations are in the F- and D-bands, up to about 100 GHz, which is about four times higher than the frequency of the TM01 surface wave. The power level of higher order mode radiation by the n = 2 beam mode decreases by a factor of hundreds from that of the n = 1 beam mode.


Keywords

oversized periodical corrugation, surface wave, higher order mode, backward wave oscillator, Smith-Purcell radiation, weakly relativistic region, cold cathode

DOI: 10.1585/pfr.8.2401085


References

  • [1] S.J. Smith and E.M. Purcell, Phys. Rev. 92, 1069 (1953).
  • [2] J. Urata et al., Phys. Rev. Lett. 80, 516 (1998).
  • [3] A. Bakhtyari et al., Phys. Rev. E 65, 066503 (2002).
  • [4] V. Kumar and K.J. Kim, Phys. Rev. E 73, 026501 (2006).
  • [5] H.L. Andrews et al., J. Appl. Phys. 105, 024904 (2009).
  • [6] W. Main et al., IEEE Trans. Plasma Sci. 22, 566 (1994).
  • [7] M.R. Amin et al., J. Phys. Soc. Jpn. 64, 4473 (1995).
  • [8] K. Ogura et al., Phys. Rev. E 53, 2726 (1996).
  • [9] A.N. Vlasov et al., IEEE Trans. Plasma Sci. 28, 550 (2000).
  • [10] K. Ogura et al., IEEJ Trans. FM 125, 733 (2005).
  • [11] S. Aoyama et al., Trans. Fusion Sci. Technol. 51, 325 (2007).
  • [12] K. Ogura et al., IEEJ Trans. FM 127, 681 (2007).
  • [13] K. Mizuno, S. Ono and Y. Shibata, IEEE Trans. Electron Devices 20, 749 (1973).
  • [14] H. Oe et al., J. Plasma Fusion Res. SERIES 8, 1477 (2009).
  • [15] D.M. Pozar, Microwave Engineering, 2nd ed. (John Wiley & Sons, Inc., New York, 1998) p.706.
  • [16] J. Benford, J.A. Swegle and E. Schamiloglu, High Power Microwaves, 2nd ed. (Taylor & Francis, New York, 2007) Chapter 8.
  • [17] G. Liu et al., J. Appl. Phys. 103, 093303 (2008).
  • [18] K. Ogura et al., J. Korean Phys. Soc. 59, 3555 (2011).

This paper may be cited as follows:

Kazuo OGURA, Kiyoyuki YAMBE, Shinji HASEGAWA, Takayuki IWASAKI, Kazumasa YAMAMOTO and Yoshihiro KOBARI, Plasma Fusion Res. 8, 2401085 (2013).