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arXiv · 1207.5581

Pulse-gated quantum dot hybrid qubit

Teck Seng Koh·John King Gamble·Mark Friesen·M. A. Eriksson·S. N. Coppersmith
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Abstract

A quantum dot hybrid qubit formed from three electrons in a double quantum dot has the potential for great speed, due to presence of level crossings where the qubit becomes charge-like. Here, we show how to take full advantage of the level crossings in a pulsed gating scheme, which decomposes the spin qubit into a series of charge transitions. We develop one and two-qubit dc quantum gates that are simpler than the previously proposed ac gates. We obtain closed form solutions for the control sequences and show that these sub-nanosecond gates can achieve high fidelities.

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Teck Seng Koh, John King Gamble, Mark Friesen, M. A. Eriksson, S. N. Coppersmith. 2012-07-24. Pulse-gated quantum dot hybrid qubit. https://doi.org/10.1103/physrevlett.109.250503

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