Direct Measurement of Nonequilibrium Electron Energy Distribution in Sub-Picosecond Laser-Heated Gold Films,

Abstract

Electron heating in metals by ultrashort laser pulses has been under intensive investigations in recent years. It is generally believed that in a very short time (< 1-2 fsec) after the optical excitation, the electrons equilibrate among themselves via the electron-electron interaction, and establish a thermal Fermi-Dirac distribution at an elevated temperature. The electron-phonon interaction operates on a longer timescale of several psec, the electrons are decoupled from lattice and it is possible to heat the electrons alone up to several thousand K. However no direct measurements of the electron energy distribution function in laser-heated metals have been reported so far. We have used ultraviolet photoemission spectroscopy to directly obtain the energy distribution function with 500 fsec time resolution.

Document Details

Document Type
Technical Report
Publication Date
May 22, 1992
Accession Number
ADP007093

Entities

People

  • J. Bokor
  • R. H. Storz
  • W. S. Fann

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Coherent Radiation
  • Distribution Functions
  • Electron Electron Interactions
  • Electron Energy
  • Electrons
  • Energy
  • Laser Pulses
  • Measurement
  • Radiation

Fields of Study

  • Physics

Readers

  • Optical Physics and Photonics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Microelectronics