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arXiv · 0707.1687

Theory of spin, electronic and transport properties of the lateral triple quantum dot molecule in a magnetic field

F. Delgado·Y. -P. Shim·M. Korkusinski·P. Hawrylak
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Abstract

We present a theory of spin, electronic and transport properties of a few-electron lateral triangular triple quantum dot molecule in a magnetic field. Our theory is based on a generalization of a Hubbard model and the Linear Combination of Harmonic Orbitals combined with Configuration Interaction method (LCHO-CI) for arbitrary magnetic fields. The few-particle spectra obtained as a function of the magnetic field exhibit Aharonov-Bohm oscillations. As a result, by changing the magnetic field it is possible to engineer the degeneracies of single-particle levels, and thus control the total spin of the many-electron system. For the triple dot with two and four electrons we find oscillations of total spin due to the singlet-triplet transitions occurring periodically in the magnetic field. In the three-electron system we find a transition from a magnetically frustrated to the spin-polarized state. We discuss the impact of these phase transitions on the addition spectrum and the spin blockade of the lateral triple quantum dot molecule.

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F. Delgado, Y. -P. Shim, M. Korkusinski, P. Hawrylak. 2007-07-11. Theory of spin, electronic and transport properties of the lateral triple quantum dot molecule in a magnetic field. https://doi.org/10.1103/physrevb.76.115332

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