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Interacting electrons in polygonal quantum dots

C E Creffield·Wolfgang Haeusler·J H Jefferson·Sarben Sarkar
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Abstract

The low-lying eigenstates of a system of two electrons confined within a two-dimensional quantum dot with a hard polygonal boundary are obtained by means of exact diagonalization. The transition from a weakly correlated charge distribution for small dots to a strongly correlated "Wigner molecule" for large dots is studied, and the behaviour at the crossover is determined. In sufficiently large dots, a recently proposed mapping to an effective charge-spin model is investigated, and is found to produce the correct ordering of the energy levels and to give a good first approximation to the size of the level spacings. We conclude that this approach is a valuable method to obtain the low energy spectrum of few-electron quantum dots.

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C E Creffield, Wolfgang Haeusler, J H Jefferson, Sarben Sarkar. 1998-10-08. Interacting electrons in polygonal quantum dots. https://doi.org/10.1103/physrevb.59.10719

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