Accession Number : ADP007093

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

Corporate Author : AT AND T BELL LABS HOLMDEL NJ

Personal Author(s) : Fann, W. S. ; Storz, R. H. ; Bokor, J.

Report Date : 22 MAY 1992

Pagination or Media Count : 4

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.

Descriptors :   *PULSED LASERS, *COHERENT OPTICAL RADIATION, *PHOTOELECTRON SPECTRA, GOLD, ELECTRON EMISSION, EXCITATION, SHORT WAVELENGTHS, COHERENT RADIATION, PHOTONS, HEATING, METAL FILMS, PHONONS, THIN FILMS, SYMPOSIA.

Subject Categories : Lasers and Masers
      Optics
      Nuclear Physics & Elementary Particle Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE