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arXiv · 1110.6622

A fast "hybrid" silicon double quantum dot qubit

Zhan Shi·C. B. Simmons·J. R. Prance·John King Gamble·Teck Seng Koh·Yun-Pil Shim·Xuedong Hu·D. E. Savage·M. G. Lagally·M. A. Eriksson·Mark Friesen·S. N. Coppersmith
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Abstract

We propose a quantum dot qubit architecture that has an attractive combination of speed and fabrication simplicity. It consists of a double quantum dot with one electron in one dot and two electrons in the other. The qubit itself is a set of two states with total spin quantum numbers $S^2=3/4$ ($S=\half$) and $S_z = -\half$, with the two different states being singlet and triplet in the doubly occupied dot. The architecture is relatively simple to fabricate, a universal set of fast operations can be implemented electrically, and the system has potentially long decoherence times. These are all extremely attractive properties for use in quantum information processing devices.

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Zhan Shi, C. B. Simmons, J. R. Prance, John King Gamble, Teck Seng Koh, Yun-Pil Shim, Xuedong Hu, D. E. Savage, M. G. Lagally, M. A. Eriksson, Mark Friesen, S. N. Coppersmith. 2011-10-30. A fast "hybrid" silicon double quantum dot qubit. https://doi.org/10.1103/physrevlett.108.140503

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