Accession Number : ADA256974


Title :   High Power Switching and Other High Power Devices


Descriptive Note : Final technical rept. 1 May 1989-31 Jul 1992


Corporate Author : UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF ELECTRICAL ENGINEERING AND ELECTROPHYSICS


Personal Author(s) : Gundersen, Martin


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a256974.pdf


Report Date : 30 Sep 1992


Pagination or Media Count : 21


Abstract : High power thyratrons and devices such as high power microwave sources have cathode-related performance limits. The report describes research of a simple, robust 'super-emissive' cathode that produces 1 0,000 A/cm2 from a macroscopic area (approx. 1 cm2), and operates with a low pressure (approx. 0. 1 torr), spatially-uniform glow plasma (density 1015 cm-3). The cathode also can operate as a hollow cathode, and is at the heart of the operation of the pseudospark and back-lighted thyratron. The physics of this hollow and super- emissive cathode is very rich. The hollow cathode geometry traps electrons in the hollow cathode backspace. The lifetime of these electrons enables them to ionize a spatially homogeneous high density glow, and this hollow cathode mode of operation is responsible for certain types of electron and ion beam behavior. A plasma cathode sheath that is formed during this phase leads to super-emissive behavior, which is responsible for high current emission. Super- emissive cathode thyratron-type switches (with higher peak current, voltage, di/dt) being developed for pulsed power switching of lasers, accelerators, high current and high coulomb transfer, Marx bank operation, transfer of technology to commercial applications, high current electron beams, and millimeter wave generation (1-100 GHz) are described.


Descriptors :   *ION BEAMS , *CATHODES , *ELECTRON BEAMS , *THYRATRONS , *SWITCHES , *PLASMA DEVICES , HIGH POWER , EMISSION , IONS , DENSITY , PHYSICS , PRESSURE , UNIFORMS , TRAPS , HEART , SWITCHING , TRANSFER , BEHAVIOR , POWER , GEOMETRY , OPERATION , HIGH DENSITY , PHASE , ELECTRONS , LASERS , LOW PRESSURE , MILLIMETER WAVES , MICROWAVES


Subject Categories : Electrical and Electronic Equipment
      Electric Power Production and Distribution
      Particle Accelerators
      Plasma Physics and Magnetohydrodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE