Electron-hole excitations and optical spectra from first principles

Journal Article · Tue Aug 15 04:00:00 EDT 2000 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.62.4927· OSTI ID:20217466

Rohlfing, Michael ^[1]; Louie, Steven G ^[2]

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1. Institut fuer Theoretische Physik II - Festkoerperphysik, Universitaet Muenster, Wilhelm-Klemm-Strasse 10, 48149 Muenster, (Germany)
2. Department of Physics, University of California, Berkeley, California 94720-7300 (United States)

We present a recently developed approach to calculate electron-hole excitations and the optical spectra of condensed matter from first principles. The key concept is to describe the excitations of the electronic system by the corresponding one- and two-particle Green's function. The method combines three computational techniques. First, the electronic ground state is treated within density-functional theory. Second, the single-particle spectrum of the electrons and holes is obtained within the GW approximation to the electron self-energy operator. Finally, the electron-hole interaction is calculated and a Bethe-Salpeter equation is solved, yielding the coupled electron-hole excitations. The resulting solutions allow the calculation of the entire optical spectrum. This holds both for bound excitonic states below the band gap, as well as for the resonant spectrum above the band gap. We discuss a number of technical developments needed for the application of the method to real systems. To illustrate the approach, we discuss the excitations and optical spectra of spatially isolated systems (atoms, molecules, and semiconductor clusters) and of extended, periodic crystals (semiconductors and insulators). (c) 2000 The American Physical Society.

• OSTI ID: 20217466
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 8 Vol. 62; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATOMS
DIELECTRIC MATERIALS
ELECTRON DENSITY
ELECTRON-HOLE COUPLING
ENERGY GAP
GREEN FUNCTION
MOLECULES
OPTICAL PROPERTIES
SEMICONDUCTOR MATERIALS
SOLID CLUSTERS
THEORETICAL DATA