Dresden 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 16: Ultrafast Phenoma II
HL 16.8: Vortrag
Montag, 20. März 2017, 17:15–17:30, POT 51
Nonspherical atomic effective pseudopotentials for surface passivation — •Anastasia Karpulevich1,2, Hanh Bui1,2, Denis Antonov3, Peng Han1, and Gabriel Bester1,2 — 1Institute of Physical Chemistry, Hamburg University, Grindelallee 117, D-20146 Hamburg, Germany — 2The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, D-22761 Hamburg, Germany — 3Physics Institute, Stuttgart University, Pfaffenwaldring 57, D-70569 Stuttgart, Germany
The quantum mechanical atomistic calculation of the electronic properties of experimental-size colloidal semiconductor nanostructures remains a challenging task. We present a method to extract accurate pseudopotentials for surface passivants, within the framework of the atomic effective pseudopotential (AEP) method [1]. AEPs are constructed by extracting the local part of the self-consistent effective pseudopotentials from DFT calculations using an analytic connection. For the passivant atoms we retain the imaginary part of the pseudopotential in the construction procedure [2]. This imaginary part reproduces an asphericity of the passivant pseudopotential and allows to model surface dipoles and corresponding band offsets. We show that these surface effects need to be taken into account to model electronic properties of quantum dots accurately. The good level of transferability, without additional computational costs, is demonstrated. The results are directly compared to large-scale DFT calculations.
[1] Cardenas J.R. et al., Physical Review B, 86(11), 115332 (2012)
[2] Karpulevich A. et al., Physical Review B, 94, 205417 (2016)