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Positron Annihilation Studies of Materials

Electron Techniques

  1. David J. Keeble1,
  2. U. Brossmann2,
  3. W. Puff2,
  4. R. Würschum2

Published Online: 12 OCT 2012

DOI: 10.1002/0471266965.com110.pub2

Characterization of Materials

Characterization of Materials

How to Cite

Keeble, D. J., Brossmann, U., Puff, W. and Würschum, R. 2012. Positron Annihilation Studies of Materials. Characterization of Materials. 1–28.

Author Information

  1. 1

    School of Engineering, Physics, and Mathematics, University of Dundee, Dundee, UK

  2. 2

    Technische Universität Graz, Institut für Technische Physik, Graz, Austria

Publication History

  1. Published Online: 12 OCT 2012

Abstract

Positron annihilation provides sensitive and versatile probe techniques in materials science that can characterize electronic structure and vacancy-type, open volume, defects. The techniques utilize the information carried by the photons that result from the quantum relativistic process of the annihilation of a positron with its antiparticle the electron. For the implanted positron, the time to the annihilation event with a host electron depends on the electron density of the local environment probed. Annihilation normally results in the conversion to two anticolinear γ photons, this emitted radiation carries information on the momentum of the electron -positron pair at the instant of annihilation.

The present article focuses on the standard e+ annihilation methods applied to the study of defects in materials. Current developments in e+ annihilation are briefly described.

Keywords:

  • vacancies;
  • crystal defects;
  • open-volume defects;
  • electron momentum;
  • Doppler broadening;
  • positron lifetime spectroscopy;
  • angular correlation of annihilation radiation (ACAR);
  • positron beam techniques