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Updated: Sep 21, 2025

Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Atomic-Site-Specific Surface Valence-Band Structure from X-Ray Standing-Wave Excited Photoemission
Yanna Chen1, Leighton O Jones2, Tien Lin Lee3
1Department of Materials Science and Engineering, Northwestern University, Illinois 60208, USA.
Abstract:
X-ray standing-wave (XSW) excited photoelectron emission was used to measure the site-specific valence band (VB) for ½ monolayer (ML) Pt grown on a SrTiO_{3} (001) surface. The XSW induced modulations in the core level (CL), and VB photoemission from the surface and substrate atoms were monitored for three hkl substrate Bragg reflections. The XSW CL analysis shows the Pt to have a face-centered-cubic-like cube-on-cube epitaxy with the substrate. The XSW VB information compares well to a density functional theory calculated projected density of states from the surface and substrate atoms. Overall, this Letter represents a novel method for determining the contribution to the density of states by valence electrons from specific atomic surface sites.
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