Berlin 2008 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 26: Methods: Electronic Structure Theory

O 26.5: Vortrag

Dienstag, 26. Februar 2008, 12:15–12:30, MA 042

Electronic properties of PbTe/CdTe(100) interfaces — •Roman Leitsmann and Friedhelm Bechstedt — Institut für Festkörpertheorie und -optik, Friedrich-Schiller Universität Jena

Previously studied semiconductor interfaces often consist of chemically different materials with the same crystallographic structure. Usually they are influenced by lattice-constant mismatch and the polarity of adjacent surfaces. Here we investigate the electronic structure of interfaces between highly ionic crystals with different crystal structure but nearly identical cubic lattice constants by first principles total energy calculations in the repeated slab approximation. The interfaces are strongly influenced by electrostatic fields. As a prototypical example we investigate the structural well defined polar PbTe/CdTe(100) interfaces [1,2,3].

We develop four different different slab models to calculate the band offsets and projected interface band-structures. These models are used to investigate the electronic properties. The occurrence of interface states is studied versus the different approaches. Moreover we discuss the reliability of the four approaches for the description of different experimental situations.

[1] W. Heiss et al., APL 88, 192109 (2006) [2] R. Leitsmann et al., New J. Phys. 8, 317 (2006) [3] R. Leitsmann et al., PRB 74, 085309 (2006)