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Optically-controlled logic gates for two spin qubits in vertically-coupled quantum dots

C. Emary·L. J. Sham
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Abstract

We describe an interaction mechanism between electron spins in a vertically-stacked double quantum dot that can be used for controlled two-qubit operations. This interaction is mediated by excitons confined within, and delocalized over, the double dot. We show that gates equivalent to the SQRT-SWAP gate can be obtained in times much less than the exciton relaxation time and that the negative effects of hole-mixing and spontaneous emission do not seriously affect these results.

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C. Emary, L. J. Sham. 2007-03-22. Optically-controlled logic gates for two spin qubits in vertically-coupled quantum dots. https://doi.org/10.1103/physrevb.75.125317

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