Electronic excitations of the H:Si(001)-(2x1) monohydride surface: First-principles calculations

Journal Article · Sun Oct 15 04:00:00 EDT 2006 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.74.155405· OSTI ID:20853769

Nengping, Wang ^[1]; Rohlfing, Michael ^[2]; Krueger, Peter; Pollmann, Johannes ^[3]

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1. School of Engineering and Science, International University Bremen, P.O. Box 750561, 28725 Bremen (Germany)
2. Fachbereich Physik, Universitaet Osnabrueck, 49069 Osnabrueck (Germany)
3. Institut fuer Festkoerpertheorie, Universitaet Muenster, 48149 Muenster (Germany)

We investigate electronic excitations of the H:Si(001)-(2x1) monohydride surface using first-principles approaches. Density-functional theory is used to calculate the ground-state geometry of the system. The quasiparticle band structure is calculated within the GW approximation. Taking the electron-hole interaction into account, electron-hole pair states and optical excitations are obtained from the solution of the Bethe-Salpeter equation for the electron-hole two-particle Green's function. In this work we focus, in particular, on localized excitations of the silicon-hydrogen bonds at the surface layer. These excitations give rise to an outward-directed force on the hydrogen atoms, which may well explain their optically induced desorption from the surface as observed in recent experiments. The localization of the excitation is described by an artificial confinement potential in addition to standard many-body perturbation theory.

• OSTI ID: 20853769
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 15 Vol. 74; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
ATOMS
BETHE-SALPETER EQUATION
CHEMICAL BONDS
DENSITY FUNCTIONAL METHOD
DESORPTION
EXCITATION
GREEN FUNCTION
GROUND STATES
HOLES
HYDROGEN
LAYERS
MANY-BODY PROBLEM
MATHEMATICAL SOLUTIONS
PERTURBATION THEORY
POTENTIALS
QUASI PARTICLES
SEMICONDUCTOR MATERIALS
SILICON
SURFACES