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Intermediate Low Spin States in a Few-electron Quantum Dot in the $ν\le 1$ Regime

Y. Nishi·P. A. Maksym·D. G. Austing·T. Hatano·L. P. Kouwenhoven·H. Aoki·S. Tarucha
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Abstract

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 $ν\le 1$. We measure excitation spectra and find ground state transitions beyond the maximum density droplet ($ν=1$) 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.

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Y. Nishi, P. A. Maksym, D. G. Austing, T. Hatano, L. P. Kouwenhoven, H. Aoki, S. Tarucha. 2005-12-12. Intermediate Low Spin States in a Few-electron Quantum Dot in the $ν\le 1$ Regime. https://doi.org/10.1103/physrevb.74.033306

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