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Optically Probing Spin and Charge Interactions in an Tunable Artificial Molecule

H. J. Krenner·E. C. Clark·T. Nakaoka·M. Bichler·C. Scheurer·G. Abstreiter·J. J. Finley
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Abstract

We optically probe and electrically control a single artificial molecule containing a well defined number of electrons. Charge and spin dependent inter-dot quantum couplings are probed optically by adding a single electron-hole pair and detecting the emission from negatively charged exciton states. Coulomb and Pauli blockade effects are directly observed and hybridization and electrostatic charging energies are independently measured. The inter-dot quantum coupling is confirmed to be mediated predominantly by electron tunneling. Our results are in excellent accord with calculations that provide a complete picture of negative excitons and few electron states in quantum dot molecules.

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H. J. Krenner, E. C. Clark, T. Nakaoka, M. Bichler, C. Scheurer, G. Abstreiter, J. J. Finley. 2006-07-18. Optically Probing Spin and Charge Interactions in an Tunable Artificial Molecule. https://doi.org/10.1103/physrevlett.97.076403

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