Intermediate Low Spin States in a Few-electron Quantum Dot in the ν ≤ 1 Regime

Physical Review B (Impact Factor: 3.74). 12/2005; 74(3). DOI: 10.1103/PhysRevB.74.033306
Source: arXiv


We study the effects of electron-electron interactions in a circular few-electron vertical quantum dot in such a strong magnetic field that the filling factor $\nu\le 1$. We measure excitation spectra and find ground state transitions beyond the maximum density droplet ($\nu=1$) region. We compare the observed spectra with those calculated by exact diagonalization to identify the ground state quantum numbers, and find that intermediate low-spin states occur between adjacent spin-polarized magic number states. Comment: 4 pages, 4 figures

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