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Correlations between Ground and Excited State Spectra of a Quantum Dot

D. R. Stewart·D. Sprinzak·C. M. Marcus·C. I. Duruoz·J. S. Harris Jr
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Abstract

We have studied the ground and excited state spectra of a semiconductor quantum dot for successive numbers of electron occupancy using linear and nonlinear magnetoconductance measurements. We present the first observation of direct correlation between the mth excited state of the N electron system and the ground state of the N+m electron system for m up to 4. Results are consistent with a non-spin-degenerate single particle picture of the filling of levels. Electron-electron interaction effects are also observed as a perturbation to this model. Magnetoconductance fluctuations of ground states are shown as anticrossings where wavefunction characteristics are exchanged between adjacent levels.

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D. R. Stewart, D. Sprinzak, C. M. Marcus, C. I. Duruoz, J. S. Harris Jr. 1997-10-30. Correlations between Ground and Excited State Spectra of a Quantum Dot. https://doi.org/10.1126/science.278.5344.1784

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