AVS 45th International Symposium
    Magnetic Interfaces and Nanostructures Technical Group Thursday Sessions
       Session MI-ThA

Paper MI-ThA3
Spin-Polarized Quantum Well States

Thursday, November 5, 1998, 2:40 pm, Room 324/325

Session: Structure & Magnetism of Surfaces & Interfaces
Presenter: K.N. Altmann, Synchrotron Radiation Center, Univ. of Wisconsin, Madison
Authors: K.N. Altmann, Synchrotron Radiation Center, Univ. of Wisconsin, Madison
W.L. O'Brien, Synchrotron Radiation Center, Univ. of Wisconsin, Madison
D.J. Seo, Synchrotron Radiation Center, Univ. of Wisconsin, Madison
J. McKay, Synchrotron Radiation Center, Univ. of Wisconsin, Madison
F.J. Himpsel, University of Wisconsin, Madison
P. Segovia, Univ. Autonoma Madrid, Spain
A. Mascaraque, Univ. Autonoma Madrid, Spain
E.G. Michel, Univ. Autonoma Madrid, Spain
A. Naermann, Univ. del Pais Vasco, San Sebastian, Spain
J.E. Ortega, Univ. del Pais Vasco, San Sebastian, Spain
Correspondent: Click to Email
Quantum well states are intimately connected to the oscillatory magnetic coupling observed in magnetic multilayers.@footnote 1,2,3@ The spin-polarization of these states is non-trivial since they reside in a non-magnetic spacer material. We have grown Cu/Co/Cu-(100) quantum wells in a chamber containing RHEED, SMOKE, MBE, and sputtering facilities. The high quality of our fcc-Co(100) layers is evidenced by the extremely low coercivity of < 1 Oe, which indicates minimal pinning of the domains at defects. These films were transferred in situ to a spin-polarized, angle-resolved photoemission system that uses undulator radiation from the SRC. Quantum well states with s,p and d character were observed when depositing films with sharp interfaces at low temperature and annealing them to room temperature. Also, a surprisingly-strong photon energy dependence was observed, even at energies of 70-80 eV, which needs a rethinking of the excitation process for "two-dimensional" quantum well states. Some of the quantum well states appear to be split, either due to multiple layer thicknesses, or due to a highly-unusual "inverted" magnetic splitting. Scanning tunneling spectroscopy measurements are in progress to find the layer-by-layer change in the energy of quantum well states. @FootnoteText@ @footnote 1@J.E. Ortega and F.J. Himpsel, Phys. Rev. Lett. 69, 844 (1992). @footnote 2@P. Segovia, E.G. Michel, and J.E. Ortega, Phys. Rev. Lett. 77, 3455 (1996). @footnote 3@F.J. Himpsel, J.E. Ortega, G.J. Mankey, and R.F. Willis, Adv. Phys., in press.