Low energy electron diffraction with position-sensitive detection: Intensity measurements and comparison with positron diffraction for NaF(001) |
| |
Affiliation: | 1. IBM T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598, United States;2. Laboratory for Physical Sciences, 8050 Greenmead Drive, College Park, MD 20740, United States;1. Huygens-Kamerlingh Onnes Laboratorium, Leiden Institute of Physics, Leiden University, Niels Bohrweg 2, P.O. Box 9504, RA Leiden NL-2300, Netherlands;2. IBM T. J. Watson Research Center, 1101 Kitchawan Road, P.O. Box 218, Yorktown Heights, New York, New York 10598, USA;1. Leiden Institute of Physics, Niels Bohrweg2, Leiden, the Netherlands;2. IBM T.J.Watson Research Center, Yorktown Heights, New York 10598, United States |
| |
Abstract: | A novel low energy electron diffraction (LEED) system incorporating a position-sensitive detector has been used to measure beam intensities as a function of incident electron energy. The detector characteristics, and the control of the incident beam focus and current are described. The (0,0)-beam intensity for NaF(001) surface was measured over the incident energy range of 2–150 eV, and the results were compared with the corresponding results for low energy positron diffraction (LEPD) [A.P. Mills and W.S. Crane, Phys. Rev. B31 (1985) 3988] as well as earlier LEED results. The LEED plots were found to contain two types of peak not present in corresponding LEPD ones: (a) narrow peaks attributable to beam-threshold interferences, and (b) odd-order Bragg peaks. The absences of these types of peak in LEPD are attributed tentatively to (a) the large incident angular divergence in the LEPD measurement cited, and (b) the relatively weak scattering of low energy positrons by Na+ ions, respectively. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|