Laser heating of air plasmas seeded by ultrashort pulse filaments

• Published in: 2009 IEEE International Conference on Plasma Science - Abstracts p. 1
• Main Authors: Gordon, D.F., Sprangle, P., Ting, A., Helle, M.H., Hafizi, B., Zigler, A.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-06-2009
• Subjects: Chemical lasers; Electric breakdown; Electrons; Heating; Laser theory; Neodymium; Optical pulses; Physics; Plasma chemistry; Plasma sources
• ISBN: 9781424426171; 1424426170
• ISSN: 0730-9244; 2576-7208
• DOI: 10.1109/PLASMA.2009.5227669

The air plasma produced by an ultrashort pulse laser filament can be used as a source of seed electrons for subsequent heating and breakdown by a higher energy long pulse laser. In this way, the threshold intensity for breakdown can be effectively lowered, raising the possibility of producing a bright, hot air plasma at a remote location. The physics of this process is examined experimentally and numerically. The experiment utilizes a 500 fs, 100 mJ pulse from a Nd: glass laser to produce the seed plasma, and a 50 ns, 1 J pulse from a Nd:YAG laser to heat the air. Radially resolved hydrodynamics calculations with detailed air chemistry are carried out to support the experiment.