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Donor Centers and Absorption Spectra in Quantum Dots

Jaime Zaratiegui García·Pekka Pietiläinen·Petteri Hyvönen
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Abstract

We have studied the electronic properties and optical absorption spectra of three different cases of donor centers, D^{0}, D^{-} and D^{2-}, which are subjected to a perpendicular magnetic field, using the exact diagonalization method. The energies of the lowest lying states are obtained as function of the applied magnetic field strength B and the distance zeta between the positive ion and the confinement xy-plane. Our calculations indicate that the positive ion induces transitions in the ground-state, which can be observed clearly in the absorption spectra, but as zeta goes to 0 the strength of the applied magnetic field needed for a transition to occur tends to infinity.

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Jaime Zaratiegui García, Pekka Pietiläinen, Petteri Hyvönen. 2002-09-02. Donor Centers and Absorption Spectra in Quantum Dots. https://doi.org/10.1103/physrevb.66.195324

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