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Influence of shape of quantum dots on their far-infrared absorption

Ingibjorg Magnusdottir·Vidar Gudmundsson
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Abstract

We investigate the effects of the shape of quantum dots on their far-infrared absorption in an external magnetic field by a model calculation. We focus our attention on dots with a parabolic confinement potential deviating from the common circular symmetry, and dots having circular doughnut shape. For a confinement where the generalized Kohn theorem does not hold we are able to interprete the results in terms of a mixture of a center-of-mass mode and collective modes reflecting an excitation of relative motion of the electrons. The calculations are performed within the time-dependent Hartree approximation and the results are compared to available experimental results.

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Ingibjorg Magnusdottir, Vidar Gudmundsson. 1999-07-15. Influence of shape of quantum dots on their far-infrared absorption. https://doi.org/10.1103/physrevb.60.16591

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