A polarized helium ion beam for surface electronic structure studies

This thesis describes the development of a spinpolarized He+ ion beam suitable for use as a- probe of surface electronic structure of metals. The method would represent an extension of ion neutralization spectroscopy (INS), and should provide new information on surface magnetism, electron correlation effects, and the dynamics of the ion neutralization process. Production of the polarized helium ion beam involves optically pumping helium metastable atoms in an rf electric discharge with subsequent extraction of ions created by metastable-metastable collisions. The principles of this technique and details of the experimental apparatus are presented. Ion currents of up to 1~ A were attained and optical pumping absorption measurements suggest a beam polarization of 8 to 1%. For a moderately low beam energy, about 15 eV, an ion density at the target surface of roughly 2 X 1 A-cm- with an energy spread of about 3 eV was attained. A specific experiment is proposed in which the polarized He+ beam would be used to probe the surface magnetic properties of nickel.

Name thesis:degree_name

Master of Arts

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Natural Sciences

Grantor

Rice University

Year dc:date.issued

1980

Author dc:creator

• Harrison, Allen Ray

Advisor dc:contributor.advisor

• Walters, G. King

Committee members dc:contributor.committeemember

• Dunning, F. Barry
• Rorschach, Harold E.

Statement dc:rights

• Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1911/103989

OAI identifier oai:identifier

oai:repository.rice.edu:1911/103989