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Strain-induced quantum ring hole states in a gated vertical quantum dot

Jun Liu·A. Zaslavsky·L. B. Freund
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Abstract

We have experimentally investigated the hole states in a gated vertical strained Si/SiGe quantum dot. We demonstrate the inhomogeneous strain relaxation on the lateral surface creates a ring-like potential near the perimeter of the dot, which can confine hole states exhibiting quantum ring characteristics. The magnetotunneling spectroscopy exhibits the predicted periodicity of energy states in ϕ/\phi0, but the magnitude of the energy shifts is larger than predicted by simple ring theory. Our results suggest a new way to fabricate and study quantum ring structures.

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Jun Liu, A. Zaslavsky, L. B. Freund. 2002-04-22. Strain-induced quantum ring hole states in a gated vertical quantum dot. https://doi.org/10.1103/physrevlett.89.096804

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