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Title: A pulsed electron gun for ultrafast electron diffraction at surfaces

Abstract

The construction of a pulsed electron gun for ultrafast reflection high-energy electron diffraction experiments at surfaces is reported. Special emphasis is placed on the characterization of the electron source: a photocathode, consisting of a 10 nm thin Au film deposited onto a sapphire substrate. Electron pulses are generated by the illumination of the film with ultraviolet laser pulses of femtosecond duration. The photoelectrons are emitted homogeneously across the photocathode with an energy distribution of 0.1 eV width. After leaving the Au film, the electrons are accelerated to kinetic energies of up to 15 keV. Focusing is accomplished by an electrostatic lens. The temporal resolution of the experiment is determined by the probing time of the electrons traveling across the surface which is about 30 ps. However, the duration of the electron pulses can be reduced to less than 6 ps.

Authors:
; ; ; ; ; ; ; ;  [1]
  1. Department of Physics and Centre for Nanointegration (CeNIDE), University of Duisburg-Essen, 47048 Duisburg (Germany)
Publication Date:
OSTI Identifier:
20953242
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 1; Other Information: DOI: 10.1063/1.2431088; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ELECTRON DIFFRACTION; ELECTRON GUNS; ELECTRON SOURCES; ELECTRONS; ELECTROSTATIC LENSES; ENERGY SPECTRA; GOLD; KEV RANGE; KINETIC ENERGY; PHOTOCATHODES; PULSES; REFLECTION; SAPPHIRE; SURFACES; THIN FILMS; ULTRAVIOLET RADIATION

Citation Formats

Janzen, A., Krenzer, B., Heinz, O., Zhou, P., Thien, D., Hanisch, A., Meyer zu Heringdorf, F.-J., Linde, D. von der, and Horn von Hoegen, M. A pulsed electron gun for ultrafast electron diffraction at surfaces. United States: N. p., 2007. Web. doi:10.1063/1.2431088.
Janzen, A., Krenzer, B., Heinz, O., Zhou, P., Thien, D., Hanisch, A., Meyer zu Heringdorf, F.-J., Linde, D. von der, & Horn von Hoegen, M. A pulsed electron gun for ultrafast electron diffraction at surfaces. United States. doi:10.1063/1.2431088.
Janzen, A., Krenzer, B., Heinz, O., Zhou, P., Thien, D., Hanisch, A., Meyer zu Heringdorf, F.-J., Linde, D. von der, and Horn von Hoegen, M. Mon . "A pulsed electron gun for ultrafast electron diffraction at surfaces". United States. doi:10.1063/1.2431088.
@article{osti_20953242,
title = {A pulsed electron gun for ultrafast electron diffraction at surfaces},
author = {Janzen, A. and Krenzer, B. and Heinz, O. and Zhou, P. and Thien, D. and Hanisch, A. and Meyer zu Heringdorf, F.-J. and Linde, D. von der and Horn von Hoegen, M.},
abstractNote = {The construction of a pulsed electron gun for ultrafast reflection high-energy electron diffraction experiments at surfaces is reported. Special emphasis is placed on the characterization of the electron source: a photocathode, consisting of a 10 nm thin Au film deposited onto a sapphire substrate. Electron pulses are generated by the illumination of the film with ultraviolet laser pulses of femtosecond duration. The photoelectrons are emitted homogeneously across the photocathode with an energy distribution of 0.1 eV width. After leaving the Au film, the electrons are accelerated to kinetic energies of up to 15 keV. Focusing is accomplished by an electrostatic lens. The temporal resolution of the experiment is determined by the probing time of the electrons traveling across the surface which is about 30 ps. However, the duration of the electron pulses can be reduced to less than 6 ps.},
doi = {10.1063/1.2431088},
journal = {Review of Scientific Instruments},
number = 1,
volume = 78,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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