Necessary conditions for the homogeneous formation of a volume avalanche discharge with specific applications to rare gas-halide excimer laser discharges

Thesis/Dissertation · Mon Jan 01 00:00:00 EST 1979

OSTI ID:5331457

Levatter, J I

Self-sustained/avalanche discharges are an efficient method of rare gas-halide excimer laser excitation in small systems. However, with the exceptions of the work reported here, experiments attempting to increase the laser energy output by scaling up the discharge volume and/or pulse duration have not been successful. The major problem encountered in scaling experiments has been the formation of arc channels in the discharge volume. The presence of arcing can totally disrupt proper laser operation. This problem stems from a general lack of understanding of high pressure avalanche discharge phenomena. Therefore, clarifying the basic discharge formation process and establishing a set of criteria under which a homogeneous avalanche discharge can be obtained is of central importance in defining the scaling limits of avalanche discharge lasers. The work presented here reviews the phenomena involved in high E/n (electric field to gas number density ratio) breakdown and its relationship to the formation of spatially homogeneous discharges. This relationship was first explored by A.J. Palmer in 1974. The basic requirement of his model was that the preionization density be large enough to cause an appreciable overlap of the primary electron avalanches and hence smooth out the ensuing space-charge fields to the extent that individual streamer formation would be prevented. This is the same basic model used in the more detailed discharge formation analysis developed here except that the effects of a time varying electric field caused by a finite voltage rise time and the effects due to the various electrochemical properties of the gas mixture are property taken into consideration.

• Research Organization: California Univ., San Diego, La Jolla (USA)
• OSTI ID: 5331457
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
42 ENGINEERING
GAS LASERS
ELECTRIC DISCHARGES
RARE GASES
DENSITY
ELECTRIC ARCS
ELECTRIC FIELDS
ELECTRODES
EXCITATION
GLOW DISCHARGES
HALIDES
IONIZATION
CURRENTS
ELECTRIC CURRENTS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
FLUIDS
GASES
HALOGEN COMPOUNDS
LASERS
NONMETALS
PHYSICAL PROPERTIES
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