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Molecular phases in coupled quantum dots

M. Rontani·S. Amaha·K. Muraki·F. Manghi·E. Molinari·S. Tarucha·D. G. Austing
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Abstract

We present excitation energy spectra of few-electron vertically coupled quantum dots for strong and intermediate inter-dot coupling. By applying a magnetic field, we induce ground state transitions and identify the corresponding quantum numbers by comparison with few-body calculations. In addition to atomic-like states, we find novel "molecular-like" phases. The isospin index characterizes the nature of the bond of the artificial molecule and this we control. Like spin in a single quantum dot, transitions in isospin leading to full polarization are observed with increasing magnetic field.

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M. Rontani, S. Amaha, K. Muraki, F. Manghi, E. Molinari, S. Tarucha, D. G. Austing. 2004-01-09. Molecular phases in coupled quantum dots. https://doi.org/10.1103/physrevb.69.085327

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