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arXiv · 1509.06901

Electron localization in self-assembled Si/Ge(111) quantum dots

Natalia Stepina·Aigul Zinovieva·Vladimir Zinovyev·Alexander Deryabin·Anatoly Dvurechenskii·Leonid Kulik
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Abstract

Electron localization in the Si/Ge heterosystem with Si quantum dots (QDs) was studied by transport and electron spin resonance (ESR) measurements. For Si QD structures grown on Ge(111) substrates, the ESR signal with g-factor $g=2.0022\pm0.0001$ and ESR line width $ΔH\approx1.2$ Oe was observed and attributed to the electrons localized in QDs. The g-factor value was explained by taking into account the energy band modification due to strain effects and quantum confinement. A strong Ge-Si intermixing in QD structures grown on Ge(001) is assumed to be main reason of unobserved ESR signal from QDs. The transport behavior confirms the efficient electron localization in Si QDs.

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Natalia Stepina, Aigul Zinovieva, Vladimir Zinovyev, Alexander Deryabin, Anatoly Dvurechenskii, Leonid Kulik. 2015-09-23. Electron localization in self-assembled Si/Ge(111) quantum dots. https://doi.org/10.1088/0268-1242%2F30%2F12%2F125013

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