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Symmetry of `molecular' configurations of interacting electrons in a quantum dot in strong magnetic fields

Hiroshi Imamura·Peter A. Maksym·Hideo Aoki
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Abstract

A molecular description for magic-number configurations of interacting electrons in a quantum dot in high magnetic fields developed by one of the authors has been elaborated for four, five and six electron dots. For four electrons, the magic spin-singlet states are found to alternate between two different resonating valence bond (RVB)-like states. For the five-electron spin-polarized case, the molecular description is shown to work for the known phenomenon of magic-number sequences that correspond to both the N-fold symmetric ring configuration and a $(N-1)$-fold symmetric one with a center electron. A six-electron dot is shown here to have an additional feature in which inclusion of quantum mechanical mixing between classical configurations, which are deformed and degenerate, restores the N-fold symmetry and reproduces the ground-state energy accurately.

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Hiroshi Imamura, Peter A. Maksym, Hideo Aoki. 1997-12-25. Symmetry of `molecular' configurations of interacting electrons in a quantum dot in strong magnetic fields. https://doi.org/10.1016/s0921-4526(98)00101-x

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