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Selective spin coupling through a single exciton

A. Nazir·B. W. Lovett·S. D. Barrett·T. P. Spiller·G. A. D. Briggs
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Abstract

We present a novel scheme for performing a conditional phase gate between two spin qubits in adjacent semiconductor quantum dots through delocalized single exciton states, formed through the inter-dot Foerster interaction. We consider two resonant quantum dots, each containing a single excess conduction band electron whose spin embodies the qubit. We demonstrate that both the two-qubit gate, and arbitrary single-qubit rotations, may be realized to a high fidelity with current semiconductor and laser technology.

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A. Nazir, B. W. Lovett, S. D. Barrett, T. P. Spiller, G. A. D. Briggs. 2004-10-12. Selective spin coupling through a single exciton. https://doi.org/10.1103/physrevlett.93.150502

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