Quasiparticle corrections to the electronic properties of anion vacancies at GaAs(110) and InP(110).
نویسندگان
چکیده
We propose a new method for calculating optical defect levels and thermodynamic charge-transition levels of point defects in semiconductors, which includes quasiparticle corrections to the Kohn-Sham eigenvalues of density-functional theory. Its applicability is demonstrated for anion vacancies at the (110) surfaces of III-V semiconductors. We find the (+/0) charge-transition level to be 0.49 eV above the surface valence-band maximum for GaAs(110) and 0.82 eV for InP(110). The results show a clear improvement over the local-density approximation and agree closely with an experimental analysis.
منابع مشابه
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عنوان ژورنال:
- Physical review letters
دوره 97 22 شماره
صفحات -
تاریخ انتشار 2006