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Few-electron molecular states and their transitions in a single InAs quantum dot molecule

T. Ota·M. Rontani·S. Tarucha·Y. Nakata·H. Z. Song·T. Miyazawa·T. Usuki·M. Takatsu·N. Yokoyama
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Abstract

We study electronic configurations in a single pair of vertically coupled self-assembled InAs quantum dots, holding just a few electrons. By comparing the experimental data of non-linear single-electron transport spectra in a magnetic field with many-body calculations, we identify the spin and orbital configurations to confirm the formation of molecular states by filling both the quantum mechanically coupled symmetric and anti-symmetric states. Filling of the anti-symmetric states is less favored with increasing magnetic field, and this leads to various magnetic field induced transitions in the molecular states.

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T. Ota, M. Rontani, S. Tarucha, Y. Nakata, H. Z. Song, T. Miyazawa, T. Usuki, M. Takatsu, N. Yokoyama. 2005-10-08. Few-electron molecular states and their transitions in a single InAs quantum dot molecule. https://doi.org/10.1103/physrevlett.95.236801

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