Direct Coulomb and Exchange Interaction in Artificial Atoms

Abstract

We determine the contributions from the direct Coulomb and exchange interactions to the total interaction in semiconductor artificial atoms. We tune the relative strengths of the two interactions and measure them as a function of the number of confined electrons. We find that electrons tend to have parallel spins when they occupy nearly degenerate single-particle states. We use a magnetic field to adjust the single-particle state degeneracy, and find that the spin-configurations in an arbitrary magnetic field are well explained in terms of two-electron singlet and triplet states.

4 pages, 5 figures

Cited by in corpus (77)

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• Multi-wall carbon nanotubes as quantum dots
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• Quantum Phase Transition in a Multi-Level Dot
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• Spatially resolved manipulation of single electrons in quantum dots using a scanned probe
• Conduction through a quantum dot near a singlet-triplet transition
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• Charge Distribution in a Kondo Correlated Quantum Dot
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• Spin-blockade spectroscopy of a two-level artificial molecule
• Non-equilibrium transport through a vertical quantum dot in the absence of spin-flip energy relaxation
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• Singlet-Triplet Transition in lateral Quantum Dots: A Numerical Renormalization Group Study
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• Evidence of correlation in spin excitations of few-electron quantum dots
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• Nonequilibrium dynamics of a singlet-triplet Anderson impurity near the quantum phase transition
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• Half-Integer Filling Factor States in Quantum Dots
• Theory of the spin singlet filling factor $\nu =2$ quantum Hall droplet
• Two-color Fermi liquid theory for transport through a multilevel Kondo impurity
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• Temperature dependence of electronic transport through molecular magnets in the Kondo regime
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• Kondo Effect in Mesoscopic Quantum Dots
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