IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    NBS-NIST Centennial Sunday Sessions
       Session NB-SuP

Paper NB-SuP3
Spin-Polarized Electrons at NBS/NIST@footnote *@

Sunday, October 28, 2001, 6:20 pm, Room 121

Session: NBS/NIST Centennial
Presenter: D.T. Pierce, National Institute of Standards and Technology
Authors: D.T. Pierce, National Institute of Standards and Technology
R.J. Celotta, National Institute of Standards and Technology
J. Unguris, National Institute of Standards and Technology
Correspondent: Click to Email
Over the past 25 years, the NIST Electron Physics Group has pioneered the use of spin-polarized electron measurement techniques in condensed matter and atomic physics. The work began with the development of an electron gun, based on photoemission from negative electron affinity GaAs, which produced an intense beam of electrons with easily reversible spin polarization. This allowed us to make sensitive surface magnetometry measurements such as polarized electron scattering and spin-polarized low-energy electron diffraction (SPLEED) measurements of magnetic surfaces. The spin-polarized electron gun enabled us to demonstrate the first spin-polarized version of inverse photoemission spectroscopy (SPIPES) and allowed others to add spin polarization to several surface measurement techniques including electron energy loss spectroscopy (SPEELS) and low energy electron microscopy (SPLEEM). We also developed a compact, efficient spin analyzer that is particularly well suited to measure the spin polarization of secondary electrons emitted from magnetic samples in a scanning electron microscope. This measurement technique, known as scanning electron microscopy with polarization analysis (SEMPA), provides high-resolution images of surface magnetization. SEMPA measurements have proven powerful for investigating both fundamental problems, such as interlayer exchange coupling of magnetic multilayers, and technological questions, such as the magnetic microstructure of small magnetic device elements. We describe a new SEMPA instrument designed to meet the magnetic imaging challenges of the near future. @FootnoteText@ @footnote *@Supported in part by the Office of Naval Research.