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Influence of symmetry and Coulomb-correlation effects on the optical properties of nitride quantum dots

N. Baer·S. Schulz·P. Gartner·S. Schumacher·G. Czycholl·F. Jahnke
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Abstract

The electronic and optical properties of self-assembled InN/GaN quantum dots (QDs) are investigated by means of a tight-binding model combined with configuration interaction calculations. Tight-binding single particle wave functions are used as a basis for computing Coulomb and dipole matrix elements. Within this framework, we analyze multi-exciton emission spectra for two different sizes of a lens-shaped InN/GaN QD with wurtzite crystal structure. The impact of the symmetry of the involved electron and hole one-particle states on the optical spectra is discussed in detail. Furthermore we show how the characteristic features of the spectra can be interpreted using a simplified Hamiltonian which provides analytical results for the interacting multi-exciton complexes. We predict a vanishing exciton and biexciton ground state emission for small lens-shaped InN/GaN QDs. For larger systems we report a bright ground state emission but with drastically reduced oscillator strengths caused by the quantum confined Stark effect.

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N. Baer, S. Schulz, P. Gartner, S. Schumacher, G. Czycholl, F. Jahnke. 2006-12-14. Influence of symmetry and Coulomb-correlation effects on the optical properties of nitride quantum dots. https://doi.org/10.1103/physrevb.76.075310

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