Abstract
The empirical sp3s* tight-binding method, which includes both spin-orbit coupling and strain effects, is employed to investigate the electronic properties of the strained ZnSe/ZnTe(001) superlattices (SLs) versus the biaxial strain, layer thicknesses and valence band offset (VBO). The results show that the conduction-band edge state is always represented by an electron localized within the ZnSe slabs; whereas the valence-band edge state (which is mostly a heavy hole (HH) related to ZnTe) can be controlled by the biaxial strain. In this respect, the results show the existence of a certain critical VBO (Vc ≃ 0.44 eV) separating two kinds of hole-confinement character (i.e. for VBO > Vc, the HH gets localized within the ZnTe layers and the SL is of type-II; whereas for VBO ≤ Vc, the HH has a tendency to localize at the hetero-interface and, as a consequence, the radiative efficiency is enhanced). Finally, our results are compared to some available photoluminescence data and conclusions about the structural and optical qualities of the experimental samples are drawn.
Original language | English |
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Pages (from-to) | 6513-6525 |
Number of pages | 13 |
Journal | Journal of Physics Condensed Matter |
Volume | 15 |
Issue number | 38 |
DOIs | |
Publication status | Published - Oct 1 2003 |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics