RF Laser Plasma Measurements,

Abstract

One of the major difficulties with excimer lasers has been the presence of impurities, introduced, for example, by the electrodes present in the D.C. discharge approach. Use of microwave excitation makes possible an electrodeless discharge, thereby reducing the risk of introducing impurities into the laser mix. In this approach a tube containing the laser mix is inserted in a waveguide or microwave cavity; the microwaves then break down the laser mix to form a discharge and further interact to heat that discharge. In such microwave discharges, strong fluorescence seems limited to approximately 100 ns. In the same time frame, the fluorescence has also been observed to collapse to the wall. The wall collapse may be related to the reduced fluorescence (reduced radiation area), although 'burn-up' of the lasing components seems more likely. The collapse to the wall reduces the ability to lase by decreasing the active volume. A better understanding of this effect needs to be obtained before a microwave-driven laser can be further developed. This research effort was directed towards obtaining a fundamental understanding of the collapse of the fluorescence to the tube walls. The ultimate goal is to understand the collapse sufficiently to prevent or reduce its effects; to this end, a number of basic plasma physics experiments have been carried out. A complete understanding has not yet been reached.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1984
Accession Number
ADA145936

Entities

People

  • W. M. Bollen

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Collapse
  • Electric Fields
  • Electron Density
  • Electrons
  • Excimer Lasers
  • Fluorescence
  • Frequency
  • Geometry
  • High Pressure
  • Lasers
  • Mean Free Path
  • Measurement
  • Microwaves
  • Military Research
  • Photography
  • Surface Waves
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Optical Physics and Photonics.
  • Pulsed Power and Plasma Physics.
  • Systems Analysis and Design

Technology Areas

  • Directed Energy