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arXiv · 2001.05045

Single-charge occupation in ambipolar quantum dots

A. J. Sousa de Almeida·A. Marquez Seco·T. van den Berg·B. van de Ven·F. Bruijnes·S. V. Amitonov·F. A. Zwanenburg
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Abstract

We demonstrate single-charge occupation of ambipolar quantum dots in silicon via charge sensing. We have fabricated ambipolar quantum dot (QD) devices in a silicon metal-oxide-semiconductor heterostructure comprising a single-electron transistor next to a single-hole transistor. Both QDs can be tuned to simultaneously sense charge transitions of the other. We further detect the few-electron and few-hole regimes in the QDs of our ambipolar device by active charge sensing.

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A. J. Sousa de Almeida, A. Marquez Seco, T. van den Berg, B. van de Ven, F. Bruijnes, S. V. Amitonov, F. A. Zwanenburg. 2020-01-14. Single-charge occupation in ambipolar quantum dots. https://doi.org/10.1103/physrevb.101.201301

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