R F Willis

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The spin-split Fermi-level crossings of the conduction band in Ni are mapped out by high-resolution pho-toemission and compared to the equivalent crossing in Cu. The area of the quasiparticle peak decreases rapidly below E F in Ni, but not in Cu. Majority spins have larger spectral weight at E F than minority spins, thereby enhancing the spin polarization(More)
Scanning tunneling microscopy (STM) and point-probe electrical conductivity measurements of electrochemically protonated films of the emeraldine-base form of the conducting polymer, polyaniline are reported. The conductivity varies spatially, dependent on the size (L(M) \m=~\ 200 to 300 angstroms) of granular metallic regions which relate directly to the(More)
Angle-resolved photoemission is used to determine the change in the electronic states of Ni induced by doping with Fe and Cr. Well-defined spin and k states are selected using high energy and k resolution combined with single crystal alloys. Iron suppresses the mean free path of minority spins only, while chromium suppresses both spins and decreases the(More)
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