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arXiv · 1006.0933

Quantum confinement effects in Si/Ge heterostructures with spatially ordered arrays of self-assembled quantum dots

Oleksiy B. Agafonov·Christian Dais·Detlev Grützmacher·Rolf J. Haug
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Abstract

Magnetotunneling spectroscopy was employed to probe the confinement in vertical Si/Ge double-barrier resonant tunneling diodes with regularly distributed Ge quantum dots. Their current-voltage characteristics reveal a step-like behavior in the vicinity of zero bias, indicating resonant tunneling of heavy-holes via three-dimensionally confined unoccupied hole states in Ge quantum dots. Assuming parabolic confinement we extract the strength of the confinement potential of quantum dots.

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Oleksiy B. Agafonov, Christian Dais, Detlev Grützmacher, Rolf J. Haug. 2010-06-07. Quantum confinement effects in Si/Ge heterostructures with spatially ordered arrays of self-assembled quantum dots. https://doi.org/10.1063/1.3442508

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