Novel electronic and magnetic properties of ultrathin chromium oxide films grown on Pt(111)

Journal Article · Fri May 01 04:00:00 EDT 1998 · Journal of Vacuum Science and Technology, A

DOI:https://doi.org/10.1116/1.581283· OSTI ID:342628

Robbert, P S; Geisler, H; Ventrice, Jr, C A ^[1]; van Ek, J ^[2]; Chaturvedi, S; Rodriguez, J A ^[3]; Kuhn, M; Diebold, U ^[4]

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1. Department of Physics, University of New Orleans, New Orleans, Louisiana 70148 (United States)
2. Seagate Technology, Bloomington, Minnesota 55435 (United States)
3. Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973 (United States)
4. Department of Physics, Tulane University, New Orleans, Louisiana 70118 (United States)

The growth of epitaxial metal{endash}oxide films on lattice-mismatched metal substrates often results in the formation of unique overlayer structures. In particular, epitaxial chromium oxide films grown on Pt(111) exhibit a p(2{times}2) symmetry through the first two monolayers of growth which is followed by a ({radical}3{times}{radical}3)R30{degree} phase that is attributed to the growth of a Cr{sub 2}O{sub 3}(0001) overlayer. Ultraviolet photoelectron spectroscopy measurements have been performed on the CrO{sub x}/Pt(111) system. The electronic structures of CrO{sub 2}, Cr{sub 2}O{sub 3}, and Cr{sub 3}O{sub 4} were calculated using the linear muffin-tin orbital method in the atomic sphere approximation. Comparison of the photoemission valence band spectra with the calculated density of states indicates that the CrO{sub x} initially grows in a cubic spinel Cr{sub 3}O{sub 4} structure. Beyond {approximately}0.2 monolayers, the metallic behavior of the CrO{sub x} overlayer begins a transformation to an insulating state. The measured valence emission for the p(2{times}2) phase beyond {approximately}0.2 monolayers is more consistent with either a {gamma}-Cr{sub 2}O{sub 3}(111) overlayer or possibly a reconstructed Cr{sub 2}O{sub 3}(0001) overlayer. {copyright} {ital 1998 American Vacuum Society.}

• OSTI ID: 342628
• Report Number(s): CONF-971029--
• Journal Information: Journal of Vacuum Science and Technology, A, Journal Name: Journal of Vacuum Science and Technology, A Journal Issue: 3 Vol. 16; ISSN 0734-2101; ISSN JVTAD6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMIUM OXIDES
ELECTRONIC STRUCTURE
FERRIMAGNETISM
FERROMAGNETISM
MUFFIN-TIN POTENTIAL
PHOTOEMISSION
PLATINUM
SYNCHROTRON RADIATION
THIN FILMS