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Excitation Spectra of Circular Few-Electron Quantum Dots

L. P. Kouwenhoven·T. H. Oosterkamp·M. W. S. Danoesastro·M. Eto·D. G. Austing·T. Honda·S. Tarucha
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Abstract

We study ground states and excited states in semiconductor quantum dots containing 1 to 12 electrons. For the first time, it is possible to identify the quantum numbers of the states in the excitation spectra and make a direct comparison to exact calculations. A magnetic field induces transitions between excited states and ground state. These transitions are discussed in terms of crossings between single-particle states, singlet-triplet transitions, spin polarization, and Hund's rule. Our impurity-free quantum dots allow for atomic physics experiments in magnetic field regimes not accessible for atoms.

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L. P. Kouwenhoven, T. H. Oosterkamp, M. W. S. Danoesastro, M. Eto, D. G. Austing, T. Honda, S. Tarucha. 1997-08-29. Excitation Spectra of Circular Few-Electron Quantum Dots. https://doi.org/10.1126/science.278.5344.1788

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