Improved Low-Energy Diffuse Scattering Electron-Spin Polarization Analyzer

Published

January 1, 1989

Author(s)

M Scheinfein, Daniel T. Pierce, John Unguris, Jabez J. McClelland, Robert Celotta, Michael H. Kelley

Abstract

An improved low-energy diffuse scattering electron-spin polarization analyzer is described. It is based on the low-energy (150 eV) diffuse scattering of polarized electrons from polycrystalline evaporated Au targets. By collecting large solid angles and efficiently energy filtering the scattered electrons, a maximum figure of merit, FOM=S²I/I₀=2.3¿10^-4 is achieved. Maximum measured values of the Sherman function were S=0.15. Further, the instrumental (false) asymmetry due to changes in the trajectory of the incident electron beam has been minimized by balancing the angular and displacement asymmetries. A total residual scan asymmetry as low as 0.0035/mm has been measured over 4-mm scan fields at the Au target in the detector. This instrumental asymmetry would produce a maximum error in the polarization in a SEMPA experiment of less than 0.3% for a 100-υm full-field scan. Details of the design and performance of the new detector are given.

Citation

Review of Scientific Instruments

Volume

60

Issue

1

Pub Type

Journals

Citation

Scheinfein, M. , Pierce, D. , Unguris, J. , McClelland, J. , Celotta, R. and Kelley, M. (1989), Improved Low-Energy Diffuse Scattering Electron-Spin Polarization Analyzer, Review of Scientific Instruments (Accessed December 4, 2024)