--- res: bibo_abstract: - We present a quantitative parameter-free method for calculating defect states and charge-transition levels of point defects in semiconductors. It combines the strength of density-functional theory for ground-state total energies with quasiparticle corrections to the excitation spectrum obtained from many-body perturbation theory. The latter is implemented within the G0W0 approximation, in which the electronic self-energy is constructed non-self-consistently from the Green’s function of the underlying Kohn–Sham system. The method is general and applicable to arbitrary bulk or surface defects. As an example we consider anion vacancies at the (110) surfaces of III–V semiconductors. Relative to the Kohn–Sham eigenvalues in the local-density approximation, the quasiparticle corrections open the fundamental band gap and raise the position of defect states inside the gap. As a consequence, the charge-transition levels are also pushed to higher energies, leading to close agreement with the available experimental data.@eng bibo_authorlist: - foaf_Person: foaf_givenName: Arno foaf_name: Schindlmayr, Arno foaf_surname: Schindlmayr foaf_workInfoHomepage: http://www.librecat.org/personId=458 orcid: 0000-0002-4855-071X - foaf_Person: foaf_givenName: Matthias foaf_name: Scheffler, Matthias foaf_surname: Scheffler bibo_doi: 10.1007/11690320_8 bibo_volume: 104 dct_date: 2007^xs_gYear dct_identifier: - UT:000241944900008 dct_isPartOf: - http://id.crossref.org/issn/0303-4216 - http://id.crossref.org/issn/1437-0859 - http://id.crossref.org/issn/978-3-540-33400-2 dct_language: eng dct_publisher: Springer@ dct_title: Quasiparticle calculations for point defects at semiconductor surfaces@ ...