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Coulomb blockade and Kondo effect in a few-electron silicon/silicon-germanium quantum dot

Levente J. Klein·Donald E. Savage·Mark A. Eriksson
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Abstract

Transport measurements at cryogenic temperatures through a few electron top gated quantum dot fabricated in a silicon/silicon-germanium heterostructure are reported. Variations in gate voltage induce a transition from an isolated dot toward a dot strongly coupled to the leads. In addition to Coulomb blockade, when the dot is strongly coupled to the leads, we observe the appearance of a zero bias conductance peak due to the Kondo effect. The Kondo peak splits in a magnetic field, and the splitting scales linearly with the applied field. We also observe a transition from pure Coulomb blockade to peaks with a Fano lineshape.

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Levente J. Klein, Donald E. Savage, Mark A. Eriksson. 2006-12-15. Coulomb blockade and Kondo effect in a few-electron silicon/silicon-germanium quantum dot. https://doi.org/10.1063/1.2431760

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