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Quantum phases in artificial molecules

Massimo Rontani·Filippo Troiani·Ulrich Hohenester·Elisa Molinari
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Abstract

The many-body state of carriers confined in a quantum dot is controlled by the balance between their kinetic energy and their Coulomb correlation. In coupled quantum dots, both can be tuned by varying the inter-dot tunneling and interactions. Using a theoretical approach based on the diagonalization of the exact Hamiltonian, we show that transitions between different quantum phases can be induced through inter-dot coupling both for a system of few electrons (or holes) and for aggregates of electrons and holes. We discuss their manifestations in addition energy spectra (accessible through capacitance or transport experiments) and optical spectra.

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Massimo Rontani, Filippo Troiani, Ulrich Hohenester, Elisa Molinari. 2001-05-22. Quantum phases in artificial molecules. https://doi.org/10.1016/s0038-1098(01)00226-5

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