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arXiv · 1102.4544

Si/SiGe quantum dot with superconducting single-electron transistor charge sensor

Mingyun Yuan·Feng Pan·Zhen Yang·T. J. Gilheart·Fei Chen·D. E. Savage·M. G. Lagally·M. A. Eriksson·A. J. Rimberg
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Abstract

We report a robust process for fabrication of surface-gated Si/SiGe quantum dots (QDs) with an integrated superconducting single-electron transistor (S-SET) charge sensor. A combination of a deep mesa etch and AlOx backfill is used to reduce gate leakage. After the leakage current is suppressed, Coulomb oscillations of the QD and the current-voltage characteristics of the S-SET are observed at a temperature of 0.3 K. Coupling of the S-SET to the QD is confirmed by using the S-SET to perform sensing of the QD charge state.

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Mingyun Yuan, Feng Pan, Zhen Yang, T. J. Gilheart, Fei Chen, D. E. Savage, M. G. Lagally, M. A. Eriksson, A. J. Rimberg. 2011-02-22. Si/SiGe quantum dot with superconducting single-electron transistor charge sensor. https://doi.org/10.1063/1.3572033

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