Theses and Dissertations from UMD

Permanent URI for this communityhttp://hdl.handle.net/1903/2

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a give thesis/dissertation in DRUM

More information is available at Theses and Dissertations at University of Maryland Libraries.

Browse

Filters

20151

Settings

Author: search.filters.author.Elle, JenniferSubject: search.filters.subject.Laser

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    STUDY OF THE FEMTOSECOND DYNAMICS AND SPECTROSCOPY OF LASER IONIZED PLASMAS.
    (2015) Elle, Jennifer; Milchberg, Howard M; Physics; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Ultra-short laser pulses are used to ionize gas in different configurations and study the plasma and ionization dynamics. The variation in non-linear index of refraction as a function of time is used to diagnose laser-plasma interactions. First, a proposed novel method to stimulate lasing in the atmosphere is studied. A few mJ pulse is used to ionize nitrogen gas in a long column without dissociating the molecular nitrogen. A 140ps laser is used to heat the resulting electron population in an attempt to generate a population inversion between the C3u and B3g states of molecular nitrogen. No evidence of lasing from this transition is observed. Next, a few mJ pulse is used to ionize xenon gas, creating Xe+ plasma. Ionization in Xe+ is observed far below the threshold predicted by multiphoton ionization theory due to resonant multiphoton ionization of collisionally excited states. To my knowledge, this is the first observation of resonant ionization involving multiple resonances. Finally, construction of an experiment to detect predicted birefringence in a relativistic laser-plasma interaction is described, with preliminary testing of diagnostics included.