Shack-Hartmann Electron Densitometer (SHED): An Optical System for Diagnosing Free Electron Density in Laser-Produced Plasmas

Abstract

The Shack-Hartmann Electron Densitometer is a novel method to diagnose ultrashort pulse laser produced plasmas by measuring the phase change to a probe laser beam. Free electrons in a plasma cause distortions to the phasefront of a probe laser that is measured through a lenslet array onto a camera. This method allows for superior performance in measuring minute variations in the electron density in 2 dimensions with sub picosecond time resolution. The data taken demonstrated the ability to diagnose plasmas with densities of the order of 1019 cm-3 and show the temporal evolution of the plasma long after the driving laser pulse has left. The method can be further improved by enclosing the probe beam and adding a second axis to allow for tomographic reconstruction of the electron density in 3 dimensions.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2016
Accession Number
AD1021274

Entities

People

  • Anthony Valenzuela

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Charge Coupled Devices
  • Densitometers
  • Detectors
  • Electromagnetic Radiation
  • Electron Density
  • Electrons
  • Free Electrons
  • Geometry
  • Laser Beams
  • Laser Produced Plasmas
  • Laser Pulses
  • Lasers
  • Military Research
  • Optics
  • Personal Information Managers
  • Refractive Index
  • Three Dimensional

Fields of Study

  • Physics

Readers

  • Optical Physics and Photonics.
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Microelectronics