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This is the author's final draft of the paper published as: Quantum Dots: Fundamentals, Applications, and Frontiers: Proceedings of the NATO Advanced Research Workshop on Quantum Dots: Fundamentals, Applications and Frontiers Crete, Greece, 20-24 July 2003 / edited by Bruce A. Joyce, Pantelis C. Kelires, Anton G. Naumovets, Dimitri D. Vvedensky, pp. 239-255. The final version is available from http://www.springerlink.com/content/k56545x7806611m4/. Doi: 10.1007/1-4020-3315-X_16An efficient method for calculation of self-assembled dot states within the effective mass approximation is described and its application to the calculation of Auger relaxation rates is detailed. The method is based on expansion of the dot states in a harmonic oscillator basis whose parameters are optimised to improve the convergence rate. This results in at least an order of magnitude reduction in the number of basis states required to represent electron states accurately compared to the conventional plane wave approach. Auger relaxation rates are calculated for harmonic oscillator model states and exact states for various pyramidal models. The dipole approximation, previously used to calculate Auger rates, is found to be inaccurate by a factor of around 2–3. The harmonic oscillator states do not reproduce the rates for the more realistic pyramidal models very well and even within the set of pyramidal models variations in the dot shape and size can change the rates by up to an order of magnitude. Typical Auger relaxation rates are on a picosecond timescale but the actual value is strongly dependent on the density of electrons outside the dot

Publisher: Springer

Year: 2005

DOI identifier: 10.1007/1-4020-3315-X_16

OAI identifier:
oai:lra.le.ac.uk:2381/7588

Provided by:
Leicester Research Archive

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