New insight on the role of localisation in the electronic structure of the Si(111)(7 × 7) surfaces

• DOI: 10.1038/s41598-021-94664-w
• Publication Date: 2021-07-22T10:04:09Z
• Authors: M. E. Dávila; J. Ávila; I. R. Colambo; D. B. Putungan; D. P. Woodruff; M. C. Asensio
• Keywords: Inverse photoemission spectroscopy

Abstract New angle-resolved photoelectron spectroscopy (ARPES) data, recorded at several different photon energies from the Si(111)(7 × 7) surface, show that well-known S1 and S2 surface states lie in bulk band gap are localised specific (adatom rest atom) sites on reconstructed surface. The variations photoemission intensity these as a function of polar azimuthal emission angle, incident energy, not consistent with Fermi mapping but well-described by calculations multiple elastic scattering final state. This localisation most shallowly bound state is lack significant dispersion, no evidence crossing, implying not, has been previously proposed, metallic character. Our findings highlight importance interpreting ARPES an aspect routinely ignored can lead to misleading conclusions.