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arXiv · 0711.1246

Finite-thickness effects in ground-state transitions of two-electron quantum dots

R. G. Nazmitdinov·N. S. Simonovic
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Abstract

Using the exactly solvable excitation spectrum of two-electron quantum dots with parabolic potential, we show that the inclusion of the vertical extension of the quantum dot provides a consistent description of the experimental findings of Nishi et al. [Phys.Rev.B75, 121301(R) (2007)]. We found that the second singlet-triplet transition in the ground state is a vanishing function of the lateral confinement in the three-dimensional case, while it always persists in the two-dimensional case. We show that a slight decrease of the lateral confinement leads to a formation of the Wigner molecule at low magnetic fields.

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R. G. Nazmitdinov, N. S. Simonovic. 2007-11-08. Finite-thickness effects in ground-state transitions of two-electron quantum dots. https://doi.org/10.1103/physrevb.76.193306

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