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arXiv · 2112.14245

Excitation spectra of two correlated electrons in a quantum dot

T. Ihn·C. Ellenberger·K. Ensslin·Constantine Yannouleas·Uzi Landman·D. C. Driscoll·A. C. Gossard
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Abstract

Measurements and a theoretical interpretation of the excitation spectrum of a two-electron quantum dot fabricated on a parabolic Ga[Al]As quantum well are reported. Experimentally, excited states are found beyond the well-known lowest singlet- and triplet states. These states can be reproduced in an exact diagonalization calculation of a parabolic dot with moderate in-plane anisotropy. The calculated spectra are in reasonable quantitative agreement with the measurement, and suggest that correlations between the electrons play a significant role in this system. Comparison of the exact results with the restricted Hartree-Fock and the generalized Heitler-London approach shows that the latter is more appropriate for this system because it can account for the spatial correlation of the electron states.

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T. Ihn, C. Ellenberger, K. Ensslin, Constantine Yannouleas, Uzi Landman, D. C. Driscoll, A. C. Gossard. 2021-12-28. Excitation spectra of two correlated electrons in a quantum dot. https://doi.org/10.1063/1.2730124

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