Abstract
The electronic structures of the (CdTe)NW1(ZnTe) Nab(CdTe)aNW2-ZnTe(001) symmetric and asymmetric double-quantum wells (s-DQW and a-DQW) are presented. The tight-binding sp 3s* method, with inclusion of spin-orbit coupling, is used to calculate the band-gap energy, quantum-confinement energy, carrier planar-spin-averaged wavefunction-squared amplitudes and band structures versus the barrier thickness (Nb), well widths (NW1 and N W2) and valence-band offset (VBO). Special atten- tion was given to the well-to-well coupling behaviors in both a-DQW and s-DQW and the estimation of the critical barrier thickness Lcritb corresponding to their decoupling. In the case of a-DQW, the wavefunctions of bound states are found to have strong tendency to localize in one of the two wells and, as a consequence, the decoupling occurs at Lcritb ≃ 18 Å, much shorter than the case of s-DQW (where Lcritb ≃ 38 Å). Our results of Eg are in excellent agreement with the available photoluminescence data and the structural and optical qualities of the experimental samples are discussed.
Original language | English |
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Pages (from-to) | 195-205 |
Number of pages | 11 |
Journal | Journal of Computational and Theoretical Nanoscience |
Volume | 6 |
Issue number | 1 |
DOIs | |
Publication status | Published - Jan 1 2009 |
Keywords
- Ii-vi semiconductors
- Quantum wells
- Semiconductor compunds
ASJC Scopus subject areas
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics
- Computational Mathematics
- Electrical and Electronic Engineering