Effect of non-uniform slow wave structure in a relativistic backward wave oscillator with a resonant reflector

Journal Article · Fri Nov 15 04:00:00 EST 2013 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4835335· OSTI ID:22218450

Chen, Changhua; Xiao, Renzhen; Sun, Jun; Song, Zhimin; Huo, Shaofei; Bai, Xianchen; Shi, Yanchao; Liu, Guozhi ^[1]

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1. Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

This paper provides a fresh insight into the effect of non-uniform slow wave structure (SWS) used in a relativistic backward wave oscillator (RBWO) with a resonant reflector. Compared with the uniform SWS, the reflection coefficient of the non-uniform SWS is higher, leading to a lower modulating electric field in the resonant reflector and a larger distance to maximize the modulation current. Moreover, for both types of RBWOs, stronger standing-wave field takes place at the rear part of the SWS. In addition, besides Cerenkov effects, the energy conversion process in the RBWO strongly depends on transit time effects. Thus, the matching condition between the distributions of harmonic current and standing wave field provides a profound influence on the beam-wave interaction. In the non-uniform RBWO, the region with a stronger standing wave field corresponds to a higher fundamental harmonic current distribution. Particle-in-cell simulations show that with a diode voltage of 1.02 MV and beam current of 13.2 kA, a microwave power of 4 GW has been obtained, compared to that of 3 GW in the uniform RBWO.

• OSTI ID: 22218450
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 11 Vol. 20; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
BEAM CURRENTS
COMPARATIVE EVALUATIONS
ELECTRIC FIELDS
ELECTRIC POTENTIAL
ENERGY CONVERSION
MICROWAVE RADIATION
MODULATION
OSCILLATORS
REFLECTION
RELATIVISTIC RANGE
RESONATORS
SEMICONDUCTOR DIODES
STANDING WAVES