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A Bolt-On Source of Spin Polarised Electrons for Studies of Surface Magnetism

  • Fredrik Schedin
  • Ranald Warburton
  • Geoff Thornton
Part of the Physics of Atoms and Molecules book series (PAMO)

Abstract

Experiments with spin-polarised electrons are rapidly gaining importance due to their ability to selectively measure the exchange-split majority- and minority-spin electronic states. By employing the inverse photoemission process with its small probing depth, information about surface magnetism can additionally be obtained. In this chapter a description will be given of a versatile and transportable spin-polarised electron gun for angle-resolved spin-polarised inverse photoemission spectroscopy (ARSPIPES) experiments. A GaAs(001) single crystal is employed to obtain spin-polarised electrons by photoemission with circularly polarised light. To obtain a transversely polarised beam, which has the objective of optimising the spin-dependent interaction with a sample magnetised in the surface plane, a 90° electrostatic spherical sector is used to deviate the direction but not the spin of the electrons. A set of electrostatic lenses are employed in order to transport and focus the electrons onto a target of investigation. A brief description of results obtained with this apparatus will be given.

Keywords

Photon Detector Gate Valve Spin Splitting Spin Channel Exchange Splitting 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Fredrik Schedin
    • 1
  • Ranald Warburton
    • 1
  • Geoff Thornton
    • 1
  1. 1.Interdisciplinary Research Centre in Surface Science and Chemistry DepartmentUniversity of ManchesterManchesterUK

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