Band structure of the Ca/Si(111)-(2×1) surface
2003 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 68, no 24, 245316- p.Article in journal (Refereed) Published
We have investigated the electronic structure of the Ca/Si(111)-(2×1) surface using angle-resolved photoelectron spectroscopy. Two semiconducting surface states were clearly observed in the bulk band gap, and one was found in a pocket of the bulk band projection. Qualitatively, the dispersions of the two surface states observed in the band gap agree well with theoretical dispersions for a clean Si(111)-(2×1) surface with the Seiwatz structure. Taking this result into account, we conclude that the two surface states in the band gap originate from orbitals of Si atoms that form a Seiwatz structure, and that two electrons are donated from Ca to Si per (2×1) unit cell. This conclusion supports the structure of the Ca/Si(111)-(2×1) surface proposed in the literature.
Place, publisher, year, edition, pages
2003. Vol. 68, no 24, 245316- p.
IdentifiersURN: urn:nbn:se:liu:diva-41806DOI: 10.1103/PhysRevB.68.245316ISI: 000188391900066Local ID: 59128OAI: oai:DiVA.org:liu-41806DiVA: diva2:262661