The Effects Of Electrode Geometry On Current Pulse Caused By Electrical Discharge Over An Ultra-fast Laser Filament

The time-resolved electrical conductivity of a short-pulse generated plasma filament in air was studied. Close-coupled metal electrodes were used to discharge the stored energy of a high-voltage capacitor and the resulting microsecond-scale electrical discharge was measured using fast current sensors. Significant differences in the time dependence of the current were seen with the two electrode geometries used. Using sharp-tipped electrodes additional peaks in the time-resolved conductivity were seen, relative to the single peak seen with spherical electrodes. We attribute these additional features to secondary electron collisional ionization brought about by field enhancement at the tips. Additional discrepancies in the currents measured leaving the high-voltage electrode and that returning to ground were also observed. Implications for potential laser-induced discharge applications will be discussed.

Author dc:creator

• Bubelnik, Matthew

Contributors dc:contributor

• Siders, Craig

• laser
• ultrafast
• femtosecond
• filament
• plasma
• Current Pulses
• time resolved current
• Electromagnetics and Photonics
• Optics

Language dc:language

English

Identifier

CFE0000447

OAI identifier oai:identifier

oai:stars.library.ucf.edu:etd-1289