Multiple quantum phases in artificial double-dot molecules

Massimo Rontani; F. Rossi; F. Manghi; E. Molinari

doi:10.1016/s0038-1098(99)00305-1

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arXiv · cond-mat/9906341

Multiple quantum phases in artificial double-dot molecules

Massimo Rontani·F. Rossi·F. Manghi·E. Molinari

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Abstract

We study coupled semiconductor quantum dots theoretically through a generalized Hubbard approach, where intra- and inter-dot Coulomb Correlation, as well as tunneling effects are described on the basis of realistic electron wavefunctions. We find that the ground-state configuration of vertically-coupled double dots undergoes non-trivial quantum transitions as a function of the inter-dot distance d; at intermediate values of d we predict a new phase that should be observable in the addition spectra and in the magnetization changes.

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Massimo Rontani, F. Rossi, F. Manghi, E. Molinari. 1999-06-22. Multiple quantum phases in artificial double-dot molecules. https://doi.org/10.1016/s0038-1098(99)00305-1

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