Journal ArticleDOI
The effect of electrode contamination, cleaning and conditioning on high-energy pulsed-power device performance
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TLDR
In-situ conditioning techniques to modify and eliminate the contaminants through multiple HV pulses, low base pressures, RF discharge cleaning, heating, surface coatings and ion-and electron-beam surface treatment allow access to new regimes of performance through control of plasma formation and modification of the plasma properties as discussed by the authors.Abstract:
High-energy pulsed-power devices routinely use field strengths above those at which broad-area, cathode-initiated, HV vacuum-breakdown occur (>10/sup 7/ to 3/spl times/10/sup 7/ V/m). Examples include magnetically-insulated transmission lines and current convolutes, high-current-density electron and ion diodes, high-power microwave devices and cavities and other structures for electrostatic and RF accelerators. Energy deposited in anode surfaces may exceed anode plasma thermal-desorption creation thresholds on the time scale of the pulse. Stimulated desorption by electron or photon bombardment also can lead to plasma formation on electrode or insulator surfaces. Device performance is limited above these thresholds, particularly in pulse length and energy, by the formation and expansion of neutral and plasma layers formed primarily from electrode contaminants. In-situ conditioning techniques to modify and eliminate the contaminants through multiple HV pulses, low base pressures, RF discharge cleaning, heating, surface coatings and ion- and electron-beam surface treatment allow access to new regimes of performance through control of plasma formation and modification of the plasma properties. Experimental and theoretical progress from a variety of devices and small scale experiments with a variety of treatment methods are reviewed and recommendations given for future work.read more
Citations
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Plasma physics and related challenges of millimeter-wave-to-terahertz and high power microwave generationa)
TL;DR: In this article, the contemporary plasma physics and other related issues of compact, high power mmw-to-THz sources are compared and contrasted to those of classic HPM generation, and future research challenges and opportunities are discussed.
Journal ArticleDOI
A review of the dense Z-pinch
TL;DR: A review of the basic physics of Z-pinch implosions can be found in this article, with a focus on the physics of wire arrays and their application in inertial confinement fusion.
Journal ArticleDOI
Characteristics and scaling of tungsten-wire-array z -pinch implosion dynamics at 20 MA.
M. E. Cuneo,Eduardo Waisman,Sergey Lebedev,J. P. Chittenden,William A. Stygar,Gordon A. Chandler,Roger Alan Vesey,Edmund Yu,Thomas J. Nash,David E. Bliss,G. S. Sarkisov,T. C. Wagoner,G. R. Bennett,Daniel Sinars,John L. Porter,Walter W. Simpson,L. E. Ruggles,David Franklin Wenger,Christopher Joseph Garasi,Bryan V. Oliver,R. A. Aragon,William E. Fowler,M C Hettrick,G. C. Idzorek,Duane D. Johnson,K. L. Keller,S. Lazier,J. S. McGurn,Thomas Alan Mehlhorn,T. C. Moore,D. S. Nielsen,J. Pyle,S. Speas,Kenneth W. Struve,Jose A. Torres +34 more
TL;DR: Cuneo et al. as discussed by the authors showed that very late acceleration is not a universal aspect of wire array implosions and varied the ablation period between 46% +/-2% and 71%+/-3% of the stagnation time.
Journal ArticleDOI
100 years of the physics of diodes
TL;DR: The Child-Langmuir Law (CL) as mentioned in this paper gives the maximum current that can be transported across a planar diode in the steady state, which is central to the studies of high current diodes, such as high power microwave sources, vacuum microelectronics, electron and ion sources, and high current drivers used in high energy density physics experiments.
Journal ArticleDOI
Electric field and electron orbits near a triple point
TL;DR: In this article, the authors focus on the electric field distribution at a triple point of a general geometry, as well as the electron orbits in its immediate vicinity and calculate the orbit of the first generation electrons, the seed electrons.
References
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Journal ArticleDOI
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Journal ArticleDOI
Plasma‐induced field emission and the characteristics of high‐current relativistic electron flow
TL;DR: The results of a comprehensive diode study conducted using a pulsed high-current electron accelerator are reported in this article, where time-dependent analysis of right-cylindrical graphite cathodes has shown evidence of the field emission character of the cold-cathode diode.