Ultrafast electron relaxation dynamics in laser-ionized gases observed with time-resolved THz spectroscopy

  • C. Frischkorn
  • , T. Kampfrath
  • , L. Perfetti
  • , P. Tegeder
  • , M. Wolf
  • , D. O. Gericke

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

Ultrashort broadband THz pulses are applied to probe the electron dynamics of various gases following ionization by an intense femtosecond laser pulse. The dielectric function of the plasma is found to be Drude-like and yields the temporal evolution of the density and collision rate of the free electrons. The electron decay in a plasma with molecular ions such as O2+ is much faster than in monatomic plasmas like Ar+/e- due to dissociative recombination which is only possible in molecular plasmas. However, adding a small amount of the electron scavenger SF6 to Ar substantially accelerates the electron decay and enables one to reliably determine the electronic temperature. Furthermore, anomalously high, metal-like electron collision rates are found. Kinetic plasma theory dramatically underestimates these rates pointing towards additional velocity-randomizing processes like collective excitations.

Original languageEnglish
Title of host publication33rd International Conference on Infrared and Millimeter Waves and the 16th International Conference on Terahertz Electronics, 2008, IRMMW-THz 2008
DOIs
Publication statusPublished - 31 Dec 2008
Externally publishedYes
Event33rd International Conference on Infrared and Millimeter Waves and the 16th International Conference on Terahertz Electronics, 2008, IRMMW-THz 2008 - Pasadena, CA, United States
Duration: 15 Sept 200819 Sept 2008

Publication series

Name33rd International Conference on Infrared and Millimeter Waves and the 16th International Conference on Terahertz Electronics, 2008, IRMMW-THz 2008

Conference

Conference33rd International Conference on Infrared and Millimeter Waves and the 16th International Conference on Terahertz Electronics, 2008, IRMMW-THz 2008
Country/TerritoryUnited States
CityPasadena, CA
Period15/09/0819/09/08

Fingerprint

Dive into the research topics of 'Ultrafast electron relaxation dynamics in laser-ionized gases observed with time-resolved THz spectroscopy'. Together they form a unique fingerprint.

Cite this