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arXiv · 0710.3725

Single-electron quantum dot in Si/SiGe with integrated charge-sensing

C. B. Simmons·Madhu Thalakulam·Nakul Shaji·Levente J. Klein·Hua Qin·R. H. Blick·D. E. Savage·M. G. Lagally·S. N. Coppersmith·M. A. Eriksson
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Abstract

Single-electron occupation is an essential component to measurement and manipulation of spin in quantum dots, capabilities that are important for quantum information processing. Si/SiGe is of interest for semiconductor spin qubits, but single-electron quantum dots have not yet been achieved in this system. We report the fabrication and measurement of a top-gated quantum dot occupied by a single electron in a Si/SiGe heterostructure. Transport through the quantum dot is directly correlated with charge-sensing from an integrated quantum point contact, and this charge-sensing is used to confirm single-electron occupancy in the quantum dot.

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C. B. Simmons, Madhu Thalakulam, Nakul Shaji, Levente J. Klein, Hua Qin, R. H. Blick, D. E. Savage, M. G. Lagally, S. N. Coppersmith, M. A. Eriksson. 2007-11-01. Single-electron quantum dot in Si/SiGe with integrated charge-sensing. https://doi.org/10.1063/1.2816331

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